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81 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Alexander Motin
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ffaedf0a44 |
Remove fastwrite mechanism.
Fastwrite was introduced many years ago to improve ZIL writes spread between multiple top-level vdevs by tracking number of allocated but not written blocks and choosing vdev with smaller count. It suposed to reduce ZIL knowledge about allocation, but actually made ZIL to even more actively report allocation code about the allocations, complicating both ZIL and metaslabs code. On top of that, it seems ZIO_FLAG_FASTWRITE setting in dmu_sync() was lost many years ago, that was one of the declared benefits. Plus introduction of embedded log metaslab class solved another problem with allocation rotor accounting both normal and log allocations, since in most cases those are now in different metaslab classes. After all that, I'd prefer to simplify already too complicated ZIL, ZIO and metaslab code if the benefit of complexity is not obvious. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: George Wilson <george.wilson@delphix.com> Signed-off-by: Alexander Motin <mav@FreeBSD.org> Sponsored by: iXsystems, Inc. Closes #15107 |
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Ameer Hamza
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d8011707cc |
Ignore pool ashift property during vdev attachment
Ashift can be set for a vdev only during its creation, and the top-level vdev does not change when a vdev is attached or replaced. The ashift property should not be used during attachment, as it does not allow attaching/replacing a vdev if the pool's ashift property is increased after the existing vdev was created. Instead, we should be able to attach the vdev if the attached vdev can satisfy the ashift requirement with its parent. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Alexander Motin <mav@FreeBSD.org> Signed-off-by: Ameer Hamza <ahamza@ixsystems.com> Closes #15061 |
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Alexander Motin
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8469b5aac0
|
Another set of vdev queue optimizations.
Switch FIFO queues (SYNC/TRIM) and active queue of vdev queue from time-sorted AVL-trees to simple lists. AVL-trees are too expensive for such a simple task. To change I/O priority without searching through the trees, add io_queue_state field to struct zio. To not check number of queued I/Os for each priority add vq_cqueued bitmap to struct vdev_queue. Update it when adding/removing I/Os. Make vq_cactive a separate array instead of struct vdev_queue_class member. Together those allow to avoid lots of cache misses when looking for work in vdev_queue_class_to_issue(). Introduce deadline of ~0.5s for LBA-sorted queues. Before this I saw some I/Os waiting in a queue for up to 8 seconds and possibly more due to starvation. With this change I no longer see it. I had to slightly more complicate the comparison function, but since it uses all the same cache lines the difference is minimal. For a sequential I/Os the new code in vdev_queue_io_to_issue() actually often uses more simple avl_first(), falling back to avl_find() and avl_nearest() only when needed. Arrange members in struct zio to access only one cache line when searching through vdev queues. While there, remove io_alloc_node, reusing the io_queue_node instead. Those two are never used same time. Remove zfs_vdev_aggregate_trim parameter. It was disabled for 4 years since implemented, while still wasted time maintaining the offset-sorted tree of TRIM requests. Just remove the tree. Remove locking from txg_all_lists_empty(). It is racy by design, while 2 pair of locks/unlocks take noticeable time under the vdev queue lock. With these changes in my tests with volblocksize=4KB I measure vdev queue lock spin time reduction by 50% on read and 75% on write. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Alexander Motin <mav@FreeBSD.org> Sponsored by: iXsystems, Inc. Closes #14925 |
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Alexander Motin
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70ea484e3e
|
Finally drop long disabled vdev cache.
It was a vdev level read cache, designed to aggregate many small reads by speculatively issuing bigger reads instead and caching the result. But since it has almost no idea about what is going on with exception of ZIO_FLAG_DONT_CACHE flag set by higher layers, it was found to make more harm than good, for which reason it was disabled for the past 12 years. These days we have much better instruments to enlarge the I/Os, such as speculative and prescient prefetches, I/O scheduler, I/O aggregation etc. Besides just the dead code removal this removes one extra mutex lock/unlock per write inside vdev_cache_write(), not otherwise disabled and trying to do some work. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Alexander Motin <mav@FreeBSD.org> Sponsored by: iXsystems, Inc. Closes #14953 |
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rob-wing
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3e4ed4213d
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Create zap for root vdev
And add it to the AVZ, this is not backwards compatible with older pools
due to an assertion in spa_sync() that verifies the number of ZAPs of
all vdevs matches the number of ZAPs in the AVZ.
Granted, the assertion only applies to #DEBUG builds - still, a feature
flag is introduced to avoid the assertion, com.klarasystems:vdev_zaps_v2
Notably, this allows to get/set properties on the root vdev:
% zpool set user:prop=value <pool> root-0
Before this commit, it was already possible to get/set properties on
top-level vdevs with the syntax <type>-<vdev_id> (e.g. mirror-0):
% zpool set user:prop=value <pool> mirror-0
This syntax also applies to the root vdev as it is is of type 'root'
with a vdev_id of 0, root-0. The keyword 'root' as an alias for
'root-0'.
The following tests have been added:
- zpool get all properties from root vdev
- zpool set a property on root vdev
- verify root vdev ZAP is created
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Wing <rob.wing@klarasystems.com>
Sponsored-by: Seagate Technology
Submitted-by: Klara, Inc.
Closes #14405
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Kevin Jin
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65d10bd87c
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Fix short-lived txg caused by autotrim
Current autotrim causes short-lived txg through: 1. calling txg_wait_synced() in metaslab_enable() 2. calling txg_wait_open() with should_quiesce = true This patch addresses all the issues mentioned above. A new cv, vdev_autotrim_kick_cv is added to kick autotrim activity. It will be signaled once a txg is synced so that it does not change the original autotrim pace. Also because it is a cv, the wait is interruptible which speeds up the vdev_autotrim_stop_wait() call. Finally, combining big zfs_txg_timeout, txg_wait_open() also causes delay when exporting a pool. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: jxdking <lostking2008@hotmail.com> Issue #8993 Closes #12194 |
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rob-wing
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69f024a56e
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Configure zed's diagnosis engine with vdev properties
Introduce four new vdev properties:
checksum_n
checksum_t
io_n
io_t
These properties can be used for configuring the thresholds of zed's
diagnosis engine and are interpeted as <N> events in T <seconds>.
When this property is set to a non-default value on a top-level vdev,
those thresholds will also apply to its leaf vdevs. This behavior can be
overridden by explicitly setting the property on the leaf vdev.
Note that, these properties do not persist across vdev replacement. For
this reason, it is advisable to set the property on the top-level vdev
instead of the leaf vdev.
The default values for zed's diagnosis engine (10 events, 600 seconds)
remains unchanged.
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Allan Jude <allan@klarasystems.com>
Signed-off-by: Rob Wing <rob.wing@klarasystems.com>
Sponsored-by: Seagate Technology LLC
Closes #13805
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Mariusz Zaborski
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16f0fdaddd
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Allow to control failfast
Linux defaults to setting "failfast" on BIOs, so that the OS will not retry IOs that fail, and instead report the error to ZFS. In some cases, such as errors reported by the HBA driver, not the device itself, we would wish to retry rather than generating vdev errors in ZFS. This new property allows that. This introduces a per vdev option to disable the failfast option. This also introduces a global module parameter to define the failfast mask value. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Co-authored-by: Allan Jude <allan@klarasystems.com> Signed-off-by: Allan Jude <allan@klarasystems.com> Signed-off-by: Mariusz Zaborski <mariusz.zaborski@klarasystems.com> Sponsored-by: Seagate Technology LLC Submitted-by: Klara, Inc. Closes #14056 |
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Richard Yao
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ab8d9c1783 |
Cleanup: 64-bit kernel module parameters should use fixed width types
Various module parameters such as `zfs_arc_max` were originally `uint64_t` on OpenSolaris/Illumos, but were changed to `unsigned long` for Linux compatibility because Linux's kernel default module parameter implementation did not support 64-bit types on 32-bit platforms. This caused problems when porting OpenZFS to Windows because its LLP64 memory model made `unsigned long` a 32-bit type on 64-bit, which created the undesireable situation that parameters that should accept 64-bit values could not on 64-bit Windows. Upon inspection, it turns out that the Linux kernel module parameter interface is extensible, such that we are allowed to define our own types. Rather than maintaining the original type change via hacks to to continue shrinking module parameters on 32-bit Linux, we implement support for 64-bit module parameters on Linux. After doing a review of all 64-bit kernel parameters (found via the man page and also proposed changes by Andrew Innes), the kernel module parameters fell into a few groups: Parameters that were originally 64-bit on Illumos: * dbuf_cache_max_bytes * dbuf_metadata_cache_max_bytes * l2arc_feed_min_ms * l2arc_feed_secs * l2arc_headroom * l2arc_headroom_boost * l2arc_write_boost * l2arc_write_max * metaslab_aliquot * metaslab_force_ganging * zfetch_array_rd_sz * zfs_arc_max * zfs_arc_meta_limit * zfs_arc_meta_min * zfs_arc_min * zfs_async_block_max_blocks * zfs_condense_max_obsolete_bytes * zfs_condense_min_mapping_bytes * zfs_deadman_checktime_ms * zfs_deadman_synctime_ms * zfs_initialize_chunk_size * zfs_initialize_value * zfs_lua_max_instrlimit * zfs_lua_max_memlimit * zil_slog_bulk Parameters that were originally 32-bit on Illumos: * zfs_per_txg_dirty_frees_percent Parameters that were originally `ssize_t` on Illumos: * zfs_immediate_write_sz Note that `ssize_t` is `int32_t` on 32-bit and `int64_t` on 64-bit. It has been upgraded to 64-bit. Parameters that were `long`/`unsigned long` because of Linux/FreeBSD influence: * l2arc_rebuild_blocks_min_l2size * zfs_key_max_salt_uses * zfs_max_log_walking * zfs_max_logsm_summary_length * zfs_metaslab_max_size_cache_sec * zfs_min_metaslabs_to_flush * zfs_multihost_interval * zfs_unflushed_log_block_max * zfs_unflushed_log_block_min * zfs_unflushed_log_block_pct * zfs_unflushed_max_mem_amt * zfs_unflushed_max_mem_ppm New parameters that do not exist in Illumos: * l2arc_trim_ahead * vdev_file_logical_ashift * vdev_file_physical_ashift * zfs_arc_dnode_limit * zfs_arc_dnode_limit_percent * zfs_arc_dnode_reduce_percent * zfs_arc_meta_limit_percent * zfs_arc_sys_free * zfs_deadman_ziotime_ms * zfs_delete_blocks * zfs_history_output_max * zfs_livelist_max_entries * zfs_max_async_dedup_frees * zfs_max_nvlist_src_size * zfs_rebuild_max_segment * zfs_rebuild_vdev_limit * zfs_unflushed_log_txg_max * zfs_vdev_max_auto_ashift * zfs_vdev_min_auto_ashift * zfs_vnops_read_chunk_size * zvol_max_discard_blocks Rather than clutter the lists with commentary, the module parameters that need comments are repeated below. A few parameters were defined in Linux/FreeBSD specific code, where the use of ulong/long is not an issue for portability, so we leave them alone: * zfs_delete_blocks * zfs_key_max_salt_uses * zvol_max_discard_blocks The documentation for a few parameters was found to be incorrect: * zfs_deadman_checktime_ms - incorrectly documented as int * zfs_delete_blocks - not documented as Linux only * zfs_history_output_max - incorrectly documented as int * zfs_vnops_read_chunk_size - incorrectly documented as long * zvol_max_discard_blocks - incorrectly documented as ulong The documentation for these has been fixed, alongside the changes to document the switch to fixed width types. In addition, several kernel module parameters were percentages or held ashift values, so being 64-bit never made sense for them. They have been downgraded to 32-bit: * vdev_file_logical_ashift * vdev_file_physical_ashift * zfs_arc_dnode_limit_percent * zfs_arc_dnode_reduce_percent * zfs_arc_meta_limit_percent * zfs_per_txg_dirty_frees_percent * zfs_unflushed_log_block_pct * zfs_vdev_max_auto_ashift * zfs_vdev_min_auto_ashift Of special note are `zfs_vdev_max_auto_ashift` and `zfs_vdev_min_auto_ashift`, which were already defined as `uint64_t`, and passed to the kernel as `ulong`. This is inherently buggy on big endian 32-bit Linux, since the values would not be written to the correct locations. 32-bit FreeBSD was unaffected because its sysctl code correctly treated this as a `uint64_t`. Lastly, a code comment suggests that `zfs_arc_sys_free` is Linux-specific, but there is nothing to indicate to me that it is Linux-specific. Nothing was done about that. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Jorgen Lundman <lundman@lundman.net> Reviewed-by: Ryan Moeller <ryan@iXsystems.com> Reviewed-by: Alexander Motin <mav@FreeBSD.org> Original-patch-by: Andrew Innes <andrew.c12@gmail.com> Original-patch-by: Jorgen Lundman <lundman@lundman.net> Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu> Closes #13984 Closes #14004 |
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Ameer Hamza
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55c12724d3
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zed: mark disks as REMOVED when they are removed
ZED does not take any action for disk removal events if there is no spare VDEV available. Added zpool_vdev_remove_wanted() in libzfs and vdev_remove_wanted() in vdev.c to remove the VDEV through ZED on removal event. This means that if you are running zed and remove a disk, it will be properly marked as REMOVED. Reviewed-by: Alexander Motin <mav@FreeBSD.org> Reviewed-by: Ryan Moeller <ryan@iXsystems.com> Reviewed-by: Tony Hutter <hutter2@llnl.gov> Signed-off-by: Ameer Hamza <ahamza@ixsystems.com> Closes #13797 |
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Richard Yao
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fdc2d30371
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Cleanup: Specify unsignedness on things that should not be signed
In #13871, zfs_vdev_aggregation_limit_non_rotating and zfs_vdev_aggregation_limit being signed was pointed out as a possible reason not to eliminate an unnecessary MAX(unsigned, 0) since the unsigned value was assigned from them. There is no reason for these module parameters to be signed and upon inspection, it was found that there are a number of other module parameters that are signed, but should not be, so we make them unsigned. Making them unsigned made it clear that some other variables in the code should also be unsigned, so we also make those unsigned. This prevents users from setting negative values that could potentially cause bad behaviors. It also makes the code slightly easier to understand. Mostly module parameters that deal with timeouts, limits, bitshifts and percentages are made unsigned by this. Any that are boolean are left signed, since whether booleans should be considered signed or unsigned does not matter. Making zfs_arc_lotsfree_percent unsigned caused a `zfs_arc_lotsfree_percent >= 0` check to become redundant, so it was removed. Removing the check was also necessary to prevent a compiler error from -Werror=type-limits. Several end of line comments had to be moved to their own lines because replacing int with uint_t caused us to exceed the 80 character limit enforced by cstyle.pl. The following were kept signed because they are passed to taskq_create(), which expects signed values and modifying the OpenSolaris/Illumos DDI is out of scope of this patch: * metaslab_load_pct * zfs_sync_taskq_batch_pct * zfs_zil_clean_taskq_nthr_pct * zfs_zil_clean_taskq_minalloc * zfs_zil_clean_taskq_maxalloc * zfs_arc_prune_task_threads Also, negative values in those parameters was found to be harmless. The following were left signed because either negative values make sense, or more analysis was needed to determine whether negative values should be disallowed: * zfs_metaslab_switch_threshold * zfs_pd_bytes_max * zfs_livelist_min_percent_shared zfs_multihost_history was made static to be consistent with other parameters. A number of module parameters were marked as signed, but in reality referenced unsigned variables. upgrade_errlog_limit is one of the numerous examples. In the case of zfs_vdev_async_read_max_active, it was already uint32_t, but zdb had an extern int declaration for it. Interestingly, the documentation in zfs.4 was right for upgrade_errlog_limit despite the module parameter being wrongly marked, while the documentation for zfs_vdev_async_read_max_active (and friends) was wrong. It was also wrong for zstd_abort_size, which was unsigned, but was documented as signed. Also, the documentation in zfs.4 incorrectly described the following parameters as ulong when they were int: * zfs_arc_meta_adjust_restarts * zfs_override_estimate_recordsize They are now uint_t as of this patch and thus the man page has been updated to describe them as uint. dbuf_state_index was left alone since it does nothing and perhaps should be removed in another patch. If any module parameters were missed, they were not found by `grep -r 'ZFS_MODULE_PARAM' | grep ', INT'`. I did find a few that grep missed, but only because they were in files that had hits. This patch intentionally did not attempt to address whether some of these module parameters should be elevated to 64-bit parameters, because the length of a long on 32-bit is 32-bit. Lastly, it was pointed out during review that uint_t is a better match for these variables than uint32_t because FreeBSD kernel parameter definitions are designed for uint_t, whose bit width can change in future memory models. As a result, we change the existing parameters that are uint32_t to use uint_t. Reviewed-by: Alexander Motin <mav@FreeBSD.org> Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Neal Gompa <ngompa@datto.com> Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu> Closes #13875 |
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Alexander Motin
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37f6845c6f
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Improve too large physical ashift handling
When iterating through children physical ashifts for vdev, prefer ones above the maximum logical ashift, that we can actually use, but within the administrator defined maximum. When selecting top-level vdev ashift, do not set it to the defined maximum in case physical ashift is even higher, but just ignore one. Using the maximum does not prevent misaligned writes, but reduces space efficiency. Since ZFS tries to write data sequentially and aggregates the writes, in many cases large misanigned writes may be not as bad as the space penalty otherwise. Allow internal physical ashifts for vdevs higher than SHIFT_MAX. May be one day allocator or aggregation could benefit from that. Reduce zfs_vdev_max_auto_ashift default from 16 (64KB) to 14 (16KB), so that ZFS may still use bigger ashifts up to SHIFT_MAX (64KB), but only if it really has to or explicitly told to, but not as an "optimization". There are some read-intensive NVMe SSDs that report Preferred Write Alignment of 64KB, and attempt to build RAIDZ2 of those leads to a space inefficiency that can't be justified. Instead these changes make ZFS fall back to logical ashift of 12 (4KB) by default and only warn user that it may be suboptimal for performance. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Ryan Moeller <ryan@iXsystems.com> Signed-off-by: Alexander Motin <mav@FreeBSD.org> Sponsored by: iXsystems, Inc. Closes #13798 |
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Tino Reichardt
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1d3ba0bf01
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Replace dead opensolaris.org license link
The commit replaces all findings of the link: http://www.opensolaris.org/os/licensing with this one: https://opensource.org/licenses/CDDL-1.0 Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tino Reichardt <milky-zfs@mcmilk.de> Closes #13619 |
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наб
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c70bb2f610 |
Replace *CTASSERT() with _Static_assert()
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz> Closes #12993 |
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наб
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18168da727
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module/*.ko: prune .data, global .rodata
Evaluated every variable that lives in .data (and globals in .rodata) in the kernel modules, and constified/eliminated/localised them appropriately. This means that all read-only data is now actually read-only data, and, if possible, at file scope. A lot of previously- global-symbols became inlinable (and inlined!) constants. Probably not in a big Wowee Performance Moment, but hey. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz> Closes #12899 |
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Allan Jude
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2a673e76a9
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Vdev Properties Feature
Add properties, similar to pool properties, to each vdev. This makes use of the existing per-vdev ZAP that was added as part of device evacuation/removal. A large number of read-only properties are exposed, many of the members of struct vdev_t, that provide useful statistics. Adds support for read-only "removing" vdev property. Adds the "allocating" property that defaults to "on" and can be set to "off" to prevent future allocations from that top-level vdev. Supports user-defined vdev properties. Includes support for properties.vdev in SYSFS. Co-authored-by: Allan Jude <allan@klarasystems.com> Co-authored-by: Mark Maybee <mark.maybee@delphix.com> Reviewed-by: Matthew Ahrens <mahrens@delphix.com> Reviewed-by: Mark Maybee <mark.maybee@delphix.com> Signed-off-by: Allan Jude <allan@klarasystems.com> Closes #11711 |
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Ryan Moeller
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e778b0485b
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Ratelimit deadman zevents as with delay zevents
Just as delay zevents can flood the zevent pipe when a vdev becomes unresponsive, so do the deadman zevents. Ratelimit deadman zevents according to the same tunable as for delay zevents. Enable deadman tests on FreeBSD and add a test for deadman event ratelimiting. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Don Brady <don.brady@delphix.com> Signed-off-by: Ryan Moeller <ryan@iXsystems.com> Closes #11786 |
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Andrea Gelmini
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bf169e9f15 |
Fix various typos
Correct an assortment of typos throughout the code base. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Matthew Ahrens <mahrens@delphix.com> Reviewed-by: Ryan Moeller <ryan@iXsystems.com> Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net> Closes #11774 |
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Alan Somers
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cf0977ad72 |
Parallelize vdev_validate
The runtime of vdev_validate is dominated by the disk accesses in vdev_label_read_config. Speed it up by validating all vdevs in parallel using a taskq. Sponsored by: Axcient Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Alan Somers <asomers@gmail.com> Closes #11470 |
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Alan Somers
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a0e01997ec |
Parallelize vdev_load
metaslab_init is the slowest part of importing a mature pool, and it must be repeated hundreds of times for each top-level vdev. But its speed is dominated by a few serialized disk accesses. That can lead to import times of > 1 hour for pools with many top-level vdevs on spinny disks. Speed up the import by using a taskqueue to parallelize vdev_load across all top-level vdevs. This also requires adding mutex protection to metaslab_class_t.mc_historgram. The mc_histogram fields were unprotected when that code was first written in "Illumos 4976-4984 - metaslab improvements" (OpenZFS |
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Matthew Ahrens
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aa755b3549
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Set aside a metaslab for ZIL blocks
Mixing ZIL and normal allocations has several problems:
1. The ZIL allocations are allocated, written to disk, and then a few
seconds later freed. This leaves behind holes (free segments) where the
ZIL blocks used to be, which increases fragmentation, which negatively
impacts performance.
2. When under moderate load, ZIL allocations are of 128KB. If the pool
is fairly fragmented, there may not be many free chunks of that size.
This causes ZFS to load more metaslabs to locate free segments of 128KB
or more. The loading happens synchronously (from zil_commit()), and can
take around a second even if the metaslab's spacemap is cached in the
ARC. All concurrent synchronous operations on this filesystem must wait
while the metaslab is loading. This can cause a significant performance
impact.
3. If the pool is very fragmented, there may be zero free chunks of
128KB or more. In this case, the ZIL falls back to txg_wait_synced(),
which has an enormous performance impact.
These problems can be eliminated by using a dedicated log device
("slog"), even one with the same performance characteristics as the
normal devices.
This change sets aside one metaslab from each top-level vdev that is
preferentially used for ZIL allocations (vdev_log_mg,
spa_embedded_log_class). From an allocation perspective, this is
similar to having a dedicated log device, and it eliminates the
above-mentioned performance problems.
Log (ZIL) blocks can be allocated from the following locations. Each
one is tried in order until the allocation succeeds:
1. dedicated log vdevs, aka "slog" (spa_log_class)
2. embedded slog metaslabs (spa_embedded_log_class)
3. other metaslabs in normal vdevs (spa_normal_class)
The space required for the embedded slog metaslabs is usually between
0.5% and 1.0% of the pool, and comes out of the existing 3.2% of "slop"
space that is not available for user data.
On an all-ssd system with 4TB storage, 87% fragmentation, 60% capacity,
and recordsize=8k, testing shows a ~50% performance increase on random
8k sync writes. On even more fragmented systems (which hit problem #3
above and call txg_wait_synced()), the performance improvement can be
arbitrarily large (>100x).
Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Reviewed-by: George Wilson <gwilson@delphix.com>
Reviewed-by: Don Brady <don.brady@delphix.com>
Reviewed-by: Mark Maybee <mark.maybee@delphix.com>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes #11389
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Alexander Motin
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6f5aac3ca0
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Reduce latency effects of non-interactive I/O
Investigating influence of scrub (especially sequential) on random read latency I've noticed that on some HDDs single 4KB read may take up to 4 seconds! Deeper investigation shown that many HDDs heavily prioritize sequential reads even when those are submitted with queue depth of 1. This patch addresses the latency from two sides: - by using _min_active queue depths for non-interactive requests while the interactive request(s) are active and few requests after; - by throttling it further if no interactive requests has completed while configured amount of non-interactive did. While there, I've also modified vdev_queue_class_to_issue() to give more chances to schedule at least _min_active requests to the lowest priorities. It should reduce starvation if several non-interactive processes are running same time with some interactive and I think should make possible setting of zfs_vdev_max_active to as low as 1. I've benchmarked this change with 4KB random reads from ZVOL with 16KB block size on newly written non-fragmented pool. On fragmented pool I also saw improvements, but not so dramatic. Below are log2 histograms of the random read latency in milliseconds for different devices: 4 2x mirror vdevs of SATA HDD WDC WD20EFRX-68EUZN0 before: 0, 0, 2, 1, 12, 21, 19, 18, 10, 15, 17, 21 after: 0, 0, 0, 24, 101, 195, 419, 250, 47, 4, 0, 0 , that means maximum latency reduction from 2s to 500ms. 4 2x mirror vdevs of SATA HDD WDC WD80EFZX-68UW8N0 before: 0, 0, 2, 31, 38, 28, 18, 12, 17, 20, 24, 10, 3 after: 0, 0, 55, 247, 455, 470, 412, 181, 36, 0, 0, 0, 0 , i.e. from 4s to 250ms. 1 SAS HDD SEAGATE ST14000NM0048 before: 0, 0, 29, 70, 107, 45, 27, 1, 0, 0, 1, 4, 19 after: 1, 29, 681, 1261, 676, 1633, 67, 1, 0, 0, 0, 0, 0 , i.e. from 4s to 125ms. 1 SAS SSD SEAGATE XS3840TE70014 before (microseconds): 0, 0, 0, 0, 0, 0, 0, 0, 70, 18343, 82548, 618 after: 0, 0, 0, 0, 0, 0, 0, 0, 283, 92351, 34844, 90 I've also measured scrub time during the test and on idle pools. On idle fragmented pool I've measured scrub getting few percent faster due to use of QD3 instead of QD2 before. On idle non-fragmented pool I've measured no difference. On busy non-fragmented pool I've measured scrub time increase about 1.5-1.7x, while IOPS increase reached 5-9x. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Matthew Ahrens <mahrens@delphix.com> Reviewed-by: Ryan Moeller <ryan@iXsystems.com> Signed-off-by: Alexander Motin <mav@FreeBSD.org> Sponsored-By: iXsystems, Inc. Closes #11166 |
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|
Brian Behlendorf
|
b2255edcc0
|
Distributed Spare (dRAID) Feature
This patch adds a new top-level vdev type called dRAID, which stands
for Distributed parity RAID. This pool configuration allows all dRAID
vdevs to participate when rebuilding to a distributed hot spare device.
This can substantially reduce the total time required to restore full
parity to pool with a failed device.
A dRAID pool can be created using the new top-level `draid` type.
Like `raidz`, the desired redundancy is specified after the type:
`draid[1,2,3]`. No additional information is required to create the
pool and reasonable default values will be chosen based on the number
of child vdevs in the dRAID vdev.
zpool create <pool> draid[1,2,3] <vdevs...>
Unlike raidz, additional optional dRAID configuration values can be
provided as part of the draid type as colon separated values. This
allows administrators to fully specify a layout for either performance
or capacity reasons. The supported options include:
zpool create <pool> \
draid[<parity>][:<data>d][:<children>c][:<spares>s] \
<vdevs...>
- draid[parity] - Parity level (default 1)
- draid[:<data>d] - Data devices per group (default 8)
- draid[:<children>c] - Expected number of child vdevs
- draid[:<spares>s] - Distributed hot spares (default 0)
Abbreviated example `zpool status` output for a 68 disk dRAID pool
with two distributed spares using special allocation classes.
```
pool: tank
state: ONLINE
config:
NAME STATE READ WRITE CKSUM
slag7 ONLINE 0 0 0
draid2:8d:68c:2s-0 ONLINE 0 0 0
L0 ONLINE 0 0 0
L1 ONLINE 0 0 0
...
U25 ONLINE 0 0 0
U26 ONLINE 0 0 0
spare-53 ONLINE 0 0 0
U27 ONLINE 0 0 0
draid2-0-0 ONLINE 0 0 0
U28 ONLINE 0 0 0
U29 ONLINE 0 0 0
...
U42 ONLINE 0 0 0
U43 ONLINE 0 0 0
special
mirror-1 ONLINE 0 0 0
L5 ONLINE 0 0 0
U5 ONLINE 0 0 0
mirror-2 ONLINE 0 0 0
L6 ONLINE 0 0 0
U6 ONLINE 0 0 0
spares
draid2-0-0 INUSE currently in use
draid2-0-1 AVAIL
```
When adding test coverage for the new dRAID vdev type the following
options were added to the ztest command. These options are leverages
by zloop.sh to test a wide range of dRAID configurations.
-K draid|raidz|random - kind of RAID to test
-D <value> - dRAID data drives per group
-S <value> - dRAID distributed hot spares
-R <value> - RAID parity (raidz or dRAID)
The zpool_create, zpool_import, redundancy, replacement and fault
test groups have all been updated provide test coverage for the
dRAID feature.
Co-authored-by: Isaac Huang <he.huang@intel.com>
Co-authored-by: Mark Maybee <mmaybee@cray.com>
Co-authored-by: Don Brady <don.brady@delphix.com>
Co-authored-by: Matthew Ahrens <mahrens@delphix.com>
Co-authored-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Mark Maybee <mmaybee@cray.com>
Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #10102
|
||
|
Toomas Soome
|
1db9e6e4e4
|
zfs label bootenv should store data as nvlist
nvlist does allow us to support different data types and systems. To encapsulate user data to/from nvlist, the libzfsbootenv library is provided. Reviewed-by: Arvind Sankar <nivedita@alum.mit.edu> Reviewed-by: Allan Jude <allan@klarasystems.com> Reviewed-by: Paul Dagnelie <pcd@delphix.com> Reviewed-by: Igor Kozhukhov <igor@dilos.org> Signed-off-by: Toomas Soome <tsoome@me.com> Closes #10774 |
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|
Ryan Moeller
|
6fe3498ca3
|
Import vdev ashift optimization from FreeBSD
Many modern devices use physical allocation units that are much
larger than the minimum logical allocation size accessible by
external commands. Two prevalent examples of this are 512e disk
drives (512b logical sector, 4K physical sector) and flash devices
(512b logical sector, 4K or larger allocation block size, and 128k
or larger erase block size). Operations that modify less than the
physical sector size result in a costly read-modify-write or garbage
collection sequence on these devices.
Simply exporting the true physical sector of the device to ZFS would
yield optimal performance, but has two serious drawbacks:
1. Existing pools created with devices that have different logical
and physical block sizes, but were configured to use the logical
block size (e.g. because the OS version used for pool construction
reported the logical block size instead of the physical block
size) will suddenly find that the vdev allocation size has
increased. This can be easily tolerated for active members of
the array, but ZFS would prevent replacement of a vdev with
another identical device because it now appears that the smaller
allocation size required by the pool is not supported by the new
device.
2. The device's physical block size may be too large to be supported
by ZFS. The optimal allocation size for the vdev may be quite
large. For example, a RAID controller may export a vdev that
requires read-modify-write cycles unless accessed using 64k
aligned/sized requests. ZFS currently has an 8k minimum block
size limit.
Reporting both the logical and physical allocation sizes for vdevs
solves these problems. A device may be used so long as the logical
block size is compatible with the configuration. By comparing the
logical and physical block sizes, new configurations can be optimized
and administrators can be notified of any existing pools that are
sub-optimal.
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Co-authored-by: Matthew Macy <mmacy@freebsd.org>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes #10619
|
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|
Brian Behlendorf
|
9a49d3f3d3
|
Add device rebuild feature
The device_rebuild feature enables sequential reconstruction when
resilvering. Mirror vdevs can be rebuilt in LBA order which may
more quickly restore redundancy depending on the pools average block
size, overall fragmentation and the performance characteristics
of the devices. However, block checksums cannot be verified
as part of the rebuild thus a scrub is automatically started after
the sequential resilver completes.
The new '-s' option has been added to the `zpool attach` and
`zpool replace` command to request sequential reconstruction
instead of healing reconstruction when resilvering.
zpool attach -s <pool> <existing vdev> <new vdev>
zpool replace -s <pool> <old vdev> <new vdev>
The `zpool status` output has been updated to report the progress
of sequential resilvering in the same way as healing resilvering.
The one notable difference is that multiple sequential resilvers
may be in progress as long as they're operating on different
top-level vdevs.
The `zpool wait -t resilver` command was extended to wait on
sequential resilvers. From this perspective they are no different
than healing resilvers.
Sequential resilvers cannot be supported for RAIDZ, but are
compatible with the dRAID feature being developed.
As part of this change the resilver_restart_* tests were moved
in to the functional/replacement directory. Additionally, the
replacement tests were renamed and extended to verify both
resilvering and rebuilding.
Original-patch-by: Isaac Huang <he.huang@intel.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: John Poduska <jpoduska@datto.com>
Co-authored-by: Mark Maybee <mmaybee@cray.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #10349
|
||
|
George Amanakis
|
b7654bd794
|
Trim L2ARC
The l2arc_evict() function is responsible for evicting buffers which reference the next bytes of the L2ARC device to be overwritten. Teach this function to additionally TRIM that vdev space before it is overwritten if the device has been filled with data. This is done by vdev_trim_simple() which trims by issuing a new type of TRIM, TRIM_TYPE_SIMPLE. We also implement a "Trim Ahead" feature. It is a zfs module parameter, expressed in % of the current write size. This trims ahead of the current write size. A minimum of 64MB will be trimmed. The default is 0 which disables TRIM on L2ARC as it can put significant stress to underlying storage devices. To enable TRIM on L2ARC we set l2arc_trim_ahead > 0. We also implement TRIM of the whole cache device upon addition to a pool, pool creation or when the header of the device is invalid upon importing a pool or onlining a cache device. This is dependent on l2arc_trim_ahead > 0. TRIM of the whole device is done with TRIM_TYPE_MANUAL so that its status can be monitored by zpool status -t. We save the TRIM state for the whole device and the time of completion on-disk in the header, and restore these upon L2ARC rebuild so that zpool status -t can correctly report them. Whole device TRIM is done asynchronously so that the user can export of the pool or remove the cache device while it is trimming (ie if it is too slow). We do not TRIM the whole device if persistent L2ARC has been disabled by l2arc_rebuild_enabled = 0 because we may not want to lose all cached buffers (eg we may want to import the pool with l2arc_rebuild_enabled = 0 only once because of memory pressure). If persistent L2ARC has been disabled by setting the module parameter l2arc_rebuild_blocks_min_l2size to a value greater than the size of the cache device then the whole device is trimmed upon creation or import of a pool if l2arc_trim_ahead > 0. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Adam D. Moss <c@yotes.com> Signed-off-by: George Amanakis <gamanakis@gmail.com> Closes #9713 Closes #9789 Closes #10224 |
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Paul Dagnelie
|
108a454a46
|
Add support for boot environment data to be stored in the label
Modern bootloaders leverage data stored in the root filesystem to enable some of their powerful features. GRUB specifically has a grubenv file which can store large amounts of configuration data that can be read and written at boot time and during normal operation. This allows sysadmins to configure useful features like automated failover after failed boot attempts. Unfortunately, due to the Copy-on-Write nature of ZFS, the standard behavior of these tools cannot handle writing to ZFS files safely at boot time. We need an alternative way to store data that allows the bootloader to make changes to the data. This work is very similar to work that was done on Illumos to enable similar functionality in the FreeBSD bootloader. This patch is different in that the data being stored is a raw grubenv file; this file can store arbitrary variables and values, and the scripting provided by grub is powerful enough that special structures are not required to implement advanced behavior. We repurpose the second padding area in each label to store the grubenv file, protected by an embedded checksum. We add two ioctls to get and set this data, and libzfs_core and libzfs functions to access them more easily. There are no direct command line interfaces to these functions; these will be added directly to the bootloader utilities. Reviewed-by: Pavel Zakharov <pavel.zakharov@delphix.com> Reviewed-by: Matthew Ahrens <mahrens@delphix.com> Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Paul Dagnelie <pcd@delphix.com> Closes #10009 |
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|
Brian Behlendorf
|
2c3a83701d |
Linux 5.6 compat: time_t
As part of the Linux kernel's y2038 changes the time_t type has been fully retired. Callers are now required to use the time64_t type. Rather than move to the new type, I've removed the few remaining places where a time_t is used in the kernel code. They've been replaced with a uint64_t which is already how ZFS internally handled these values. Going forward we should work towards updating the remaining user space time_t consumers to the 64-bit interfaces. Reviewed-by: Matthew Macy <mmacy@freebsd.org> Reviewed-by: Tony Hutter <hutter2@llnl.gov> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Closes #10052 Closes #10064 |
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Matthew Macy
|
da92d5cbb3 |
Add zfs_file_* interface, remove vnodes
Provide a common zfs_file_* interface which can be implemented on all platforms to perform normal file access from either the kernel module or the libzpool library. This allows all non-portable vnode_t usage in the common code to be replaced by the new portable zfs_file_t. The associated vnode and kobj compatibility functions, types, and macros have been removed from the SPL. Moving forward, vnodes should only be used in platform specific code when provided by the native operating system. Reviewed-by: Sean Eric Fagan <sef@ixsystems.com> Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Igor Kozhukhov <igor@dilos.org> Reviewed-by: Jorgen Lundman <lundman@lundman.net> Signed-off-by: Matt Macy <mmacy@FreeBSD.org> Closes #9556 |
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Paul Dagnelie
|
ca5777793e |
Reduce loaded range tree memory usage
This patch implements a new tree structure for ZFS, and uses it to
store range trees more efficiently.
The new structure is approximately a B-tree, though there are some
small differences from the usual characterizations. The tree has core
nodes and leaf nodes; each contain data elements, which the elements
in the core nodes acting as separators between its children. The
difference between core and leaf nodes is that the core nodes have an
array of children, while leaf nodes don't. Every node in the tree may
be only partially full; in most cases, they are all at least 50% full
(in terms of element count) except for the root node, which can be
less full. Underfull nodes will steal from their neighbors or merge to
remain full enough, while overfull nodes will split in two. The data
elements are contained in tree-controlled buffers; they are copied
into these on insertion, and overwritten on deletion. This means that
the elements are not independently allocated, which reduces overhead,
but also means they can't be shared between trees (and also that
pointers to them are only valid until a side-effectful tree operation
occurs). The overhead varies based on how dense the tree is, but is
usually on the order of about 50% of the element size; the per-node
overheads are very small, and so don't make a significant difference.
The trees can accept arbitrary records; they accept a size and a
comparator to allow them to be used for a variety of purposes.
The new trees replace the AVL trees used in the range trees today.
Currently, the range_seg_t structure contains three 8 byte integers
of payload and two 24 byte avl_tree_node_ts to handle its storage in
both an offset-sorted tree and a size-sorted tree (total size: 64
bytes). In the new model, the range seg structures are usually two 4
byte integers, but a separate one needs to exist for the size-sorted
and offset-sorted tree. Between the raw size, the 50% overhead, and
the double storage, the new btrees are expected to use 8*1.5*2 = 24
bytes per record, or 33.3% as much memory as the AVL trees (this is
for the purposes of storing metaslab range trees; for other purposes,
like scrubs, they use ~50% as much memory).
We reduced the size of the payload in the range segments by teaching
range trees about starting offsets and shifts; since metaslabs have a
fixed starting offset, and they all operate in terms of disk sectors,
we can store the ranges using 4-byte integers as long as the size of
the metaslab divided by the sector size is less than 2^32. For 512-byte
sectors, this is a 2^41 (or 2TB) metaslab, which with the default
settings corresponds to a 256PB disk. 4k sector disks can handle
metaslabs up to 2^46 bytes, or 2^63 byte disks. Since we do not
anticipate disks of this size in the near future, there should be
almost no cases where metaslabs need 64-byte integers to store their
ranges. We do still have the capability to store 64-byte integer ranges
to account for cases where we are storing per-vdev (or per-dnode) trees,
which could reasonably go above the limits discussed. We also do not
store fill information in the compact version of the node, since it
is only used for sorted scrub.
We also optimized the metaslab loading process in various other ways
to offset some inefficiencies in the btree model. While individual
operations (find, insert, remove_from) are faster for the btree than
they are for the avl tree, remove usually requires a find operation,
while in the AVL tree model the element itself suffices. Some clever
changes actually caused an overall speedup in metaslab loading; we use
approximately 40% less cpu to load metaslabs in our tests on Illumos.
Another memory and performance optimization was achieved by changing
what is stored in the size-sorted trees. When a disk is heavily
fragmented, the df algorithm used by default in ZFS will almost always
find a number of small regions in its initial cursor-based search; it
will usually only fall back to the size-sorted tree to find larger
regions. If we increase the size of the cursor-based search slightly,
and don't store segments that are smaller than a tunable size floor
in the size-sorted tree, we can further cut memory usage down to
below 20% of what the AVL trees store. This also results in further
reductions in CPU time spent loading metaslabs.
The 16KiB size floor was chosen because it results in substantial memory
usage reduction while not usually resulting in situations where we can't
find an appropriate chunk with the cursor and are forced to use an
oversized chunk from the size-sorted tree. In addition, even if we do
have to use an oversized chunk from the size-sorted tree, the chunk
would be too small to use for ZIL allocations, so it isn't as big of a
loss as it might otherwise be. And often, more small allocations will
follow the initial one, and the cursor search will now find the
remainder of the chunk we didn't use all of and use it for subsequent
allocations. Practical testing has shown little or no change in
fragmentation as a result of this change.
If the size-sorted tree becomes empty while the offset sorted one still
has entries, it will load all the entries from the offset sorted tree
and disregard the size floor until it is unloaded again. This operation
occurs rarely with the default setting, only on incredibly thoroughly
fragmented pools.
There are some other small changes to zdb to teach it to handle btrees,
but nothing major.
Reviewed-by: George Wilson <gwilson@delphix.com>
Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed by: Sebastien Roy seb@delphix.com
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes #9181
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|
Serapheim Dimitropoulos
|
93e28d661e |
Log Spacemap Project
= Motivation At Delphix we've seen a lot of customer systems where fragmentation is over 75% and random writes take a performance hit because a lot of time is spend on I/Os that update on-disk space accounting metadata. Specifically, we seen cases where 20% to 40% of sync time is spend after sync pass 1 and ~30% of the I/Os on the system is spent updating spacemaps. The problem is that these pools have existed long enough that we've touched almost every metaslab at least once, and random writes scatter frees across all metaslabs every TXG, thus appending to their spacemaps and resulting in many I/Os. To give an example, assuming that every VDEV has 200 metaslabs and our writes fit within a single spacemap block (generally 4K) we have 200 I/Os. Then if we assume 2 levels of indirection, we need 400 additional I/Os and since we are talking about metadata for which we keep 2 extra copies for redundancy we need to triple that number, leading to a total of 1800 I/Os per VDEV every TXG. We could try and decrease the number of metaslabs so we have less I/Os per TXG but then each metaslab would cover a wider range on disk and thus would take more time to be loaded in memory from disk. In addition, after it's loaded, it's range tree would consume more memory. Another idea would be to just increase the spacemap block size which would allow us to fit more entries within an I/O block resulting in fewer I/Os per metaslab and a speedup in loading time. The problem is still that we don't deal with the number of I/Os going up as the number of metaslabs is increasing and the fact is that we generally write a lot to a few metaslabs and a little to the rest of them. Thus, just increasing the block size would actually waste bandwidth because we won't be utilizing our bigger block size. = About this patch This patch introduces the Log Spacemap project which provides the solution to the above problem while taking into account all the aforementioned tradeoffs. The details on how it achieves that can be found in the references sections below and in the code (see Big Theory Statement in spa_log_spacemap.c). Even though the change is fairly constraint within the metaslab and lower-level SPA codepaths, there is a side-change that is user-facing. The change is that VDEV IDs from VDEV holes will no longer be reused. To give some background and reasoning for this, when a log device is removed and its VDEV structure was replaced with a hole (or was compacted; if at the end of the vdev array), its vdev_id could be reused by devices added after that. Now with the pool-wide space maps recording the vdev ID, this behavior can cause problems (e.g. is this entry referring to a segment in the new vdev or the removed log?). Thus, to simplify things the ID reuse behavior is gone and now vdev IDs for top-level vdevs are truly unique within a pool. = Testing The illumos implementation of this feature has been used internally for a year and has been in production for ~6 months. For this patch specifically there don't seem to be any regressions introduced to ZTS and I have been running zloop for a week without any related problems. = Performance Analysis (Linux Specific) All performance results and analysis for illumos can be found in the links of the references. Redoing the same experiments in Linux gave similar results. Below are the specifics of the Linux run. After the pool reached stable state the percentage of the time spent in pass 1 per TXG was 64% on average for the stock bits while the log spacemap bits stayed at 95% during the experiment (graph: sdimitro.github.io/img/linux-lsm/PercOfSyncInPassOne.png). Sync times per TXG were 37.6 seconds on average for the stock bits and 22.7 seconds for the log spacemap bits (related graph: sdimitro.github.io/img/linux-lsm/SyncTimePerTXG.png). As a result the log spacemap bits were able to push more TXGs, which is also the reason why all graphs quantified per TXG have more entries for the log spacemap bits. Another interesting aspect in terms of txg syncs is that the stock bits had 22% of their TXGs reach sync pass 7, 55% reach sync pass 8, and 20% reach 9. The log space map bits reached sync pass 4 in 79% of their TXGs, sync pass 7 in 19%, and sync pass 8 at 1%. This emphasizes the fact that not only we spend less time on metadata but we also iterate less times to convergence in spa_sync() dirtying objects. [related graphs: stock- sdimitro.github.io/img/linux-lsm/NumberOfPassesPerTXGStock.png lsm- sdimitro.github.io/img/linux-lsm/NumberOfPassesPerTXGLSM.png] Finally, the improvement in IOPs that the userland gains from the change is approximately 40%. There is a consistent win in IOPS as you can see from the graphs below but the absolute amount of improvement that the log spacemap gives varies within each minute interval. sdimitro.github.io/img/linux-lsm/StockVsLog3Days.png sdimitro.github.io/img/linux-lsm/StockVsLog10Hours.png = Porting to Other Platforms For people that want to port this commit to other platforms below is a list of ZoL commits that this patch depends on: Make zdb results for checkpoint tests consistent |
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|
Brian Behlendorf
|
1b939560be
|
Add TRIM support
UNMAP/TRIM support is a frequently-requested feature to help prevent performance from degrading on SSDs and on various other SAN-like storage back-ends. By issuing UNMAP/TRIM commands for sectors which are no longer allocated the underlying device can often more efficiently manage itself. This TRIM implementation is modeled on the `zpool initialize` feature which writes a pattern to all unallocated space in the pool. The new `zpool trim` command uses the same vdev_xlate() code to calculate what sectors are unallocated, the same per- vdev TRIM thread model and locking, and the same basic CLI for a consistent user experience. The core difference is that instead of writing a pattern it will issue UNMAP/TRIM commands for those extents. The zio pipeline was updated to accommodate this by adding a new ZIO_TYPE_TRIM type and associated spa taskq. This new type makes is straight forward to add the platform specific TRIM/UNMAP calls to vdev_disk.c and vdev_file.c. These new ZIO_TYPE_TRIM zios are handled largely the same way as ZIO_TYPE_READs or ZIO_TYPE_WRITEs. This makes it possible to largely avoid changing the pipieline, one exception is that TRIM zio's may exceed the 16M block size limit since they contain no data. In addition to the manual `zpool trim` command, a background automatic TRIM was added and is controlled by the 'autotrim' property. It relies on the exact same infrastructure as the manual TRIM. However, instead of relying on the extents in a metaslab's ms_allocatable range tree, a ms_trim tree is kept per metaslab. When 'autotrim=on', ranges added back to the ms_allocatable tree are also added to the ms_free tree. The ms_free tree is then periodically consumed by an autotrim thread which systematically walks a top level vdev's metaslabs. Since the automatic TRIM will skip ranges it considers too small there is value in occasionally running a full `zpool trim`. This may occur when the freed blocks are small and not enough time was allowed to aggregate them. An automatic TRIM and a manual `zpool trim` may be run concurrently, in which case the automatic TRIM will yield to the manual TRIM. Reviewed-by: Jorgen Lundman <lundman@lundman.net> Reviewed-by: Tim Chase <tim@chase2k.com> Reviewed-by: Matt Ahrens <mahrens@delphix.com> Reviewed-by: George Wilson <george.wilson@delphix.com> Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com> Contributions-by: Saso Kiselkov <saso.kiselkov@nexenta.com> Contributions-by: Tim Chase <tim@chase2k.com> Contributions-by: Chunwei Chen <tuxoko@gmail.com> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Closes #8419 Closes #598 |
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|
Olaf Faaland
|
3d31aad83e |
MMP writes rotate over leaves
Instead of choosing a leaf vdev quasi-randomly, by starting at the root
vdev and randomly choosing children, rotate over leaves to issue MMP
writes. This fixes an issue in a pool whose top-level vdevs have
different numbers of leaves.
The issue is that the frequency at which individual leaves are chosen
for MMP writes is based not on the total number of leaves but based on
how many siblings the leaves have.
For example, in a pool like this:
root-vdev
+------+---------------+
vdev1 vdev2
| |
| +------+-----+-----+----+
disk1 disk2 disk3 disk4 disk5 disk6
vdev1 and vdev2 will each be chosen 50% of the time. Every time vdev1
is chosen, disk1 will be chosen. However, every time vdev2 is chosen,
disk2 is chosen 20% of the time. As a result, disk1 will be sent 5x as
many MMP writes as disk2.
This may create wear issues in the case of SSDs. It also reduces the
effectiveness of MMP as it depends on the writes being evenly
distributed for the case where some devices fail or are partitioned.
The new code maintains a list of leaf vdevs in the pool. MMP records
the last leaf used for an MMP write in mmp->mmp_last_leaf. To choose
the next leaf, MMP starts at mmp->mmp_last_leaf and traverses the list,
continuing from the head if the tail is reached. It stops when a
suitable leaf is found or all leaves have been examined.
Added a test to verify MMP write distribution is even.
Reviewed-by: Tom Caputi <tcaputi@datto.com>
Reviewed-by: Kash Pande <kash@tripleback.net>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: loli10K <ezomori.nozomu@gmail.com>
Signed-off-by: Olaf Faaland <faaland1@llnl.gov>
Closes #7953
|
||
|
Serapheim Dimitropoulos
|
75058f3303 |
Remove unused vdev_t fields
The following fields from the vdev_t struct are not used anywhere. Reviewed-by: George Melikov <mail@gmelikov.ru> Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Tony Hutter <hutter2@llnl.gov> Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com> Closes #8285 |
||
|
George Wilson
|
c10d37dd9f |
zfs initialize performance enhancements
PROBLEM ======== When invoking "zpool initialize" on a pool the command will create a thread to initialize each disk. Unfortunately, it does this serially across many transaction groups which can result in commands taking a long time to return to the user and may appear hung. The same thing is true when trying to suspend/cancel the operation. SOLUTION ========= This change refactors the way we invoke the initialize interface to ensure we can start or stop the intialization in just a few transaction groups. When stopping or cancelling a vdev initialization perform it in two phases. First signal each vdev initialization thread that it should exit, then after all threads have been signaled wait for them to exit. On a pool with 40 leaf vdevs this reduces the vdev initialize stop/cancel time from ~10 minutes to under a second. The reason for this is spa_vdev_initialize() no longer needs to wait on multiple full TXGs per leaf vdev being stopped. This commit additionally adds some missing checks for the passed "initialize_vdevs" input nvlist. The contents of the user provided input "initialize_vdevs" nvlist must be validated to ensure all values are uint64s. This is done in zfs_ioc_pool_initialize() in order to keep all of these checks in a single location. Updated the innvl and outnvl comments to match the formatting used for all other new sytle ioctls. Reviewed by: Matt Ahrens <mahrens@delphix.com> Reviewed-by: loli10K <ezomori.nozomu@gmail.com> Reviewed-by: Tim Chase <tim@chase2k.com> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: George Wilson <george.wilson@delphix.com> Closes #8230 |
||
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George Wilson
|
619f097693 |
OpenZFS 9102 - zfs should be able to initialize storage devices
PROBLEM
========
The first access to a block incurs a performance penalty on some platforms
(e.g. AWS's EBS, VMware VMDKs). Therefore we recommend that volumes are
"thick provisioned", where supported by the platform (VMware). This can
create a large delay in getting a new virtual machines up and running (or
adding storage to an existing Engine). If the thick provision step is
omitted, write performance will be suboptimal until all blocks on the LUN
have been written.
SOLUTION
=========
This feature introduces a way to 'initialize' the disks at install or in the
background to make sure we don't incur this first read penalty.
When an entire LUN is added to ZFS, we make all space available immediately,
and allow ZFS to find unallocated space and zero it out. This works with
concurrent writes to arbitrary offsets, ensuring that we don't zero out
something that has been (or is in the middle of being) written. This scheme
can also be applied to existing pools (affecting only free regions on the
vdev). Detailed design:
- new subcommand:zpool initialize [-cs] <pool> [<vdev> ...]
- start, suspend, or cancel initialization
- Creates new open-context thread for each vdev
- Thread iterates through all metaslabs in this vdev
- Each metaslab:
- select a metaslab
- load the metaslab
- mark the metaslab as being zeroed
- walk all free ranges within that metaslab and translate
them to ranges on the leaf vdev
- issue a "zeroing" I/O on the leaf vdev that corresponds to
a free range on the metaslab we're working on
- continue until all free ranges for this metaslab have been
"zeroed"
- reset/unmark the metaslab being zeroed
- if more metaslabs exist, then repeat above tasks.
- if no more metaslabs, then we're done.
- progress for the initialization is stored on-disk in the vdev’s
leaf zap object. The following information is stored:
- the last offset that has been initialized
- the state of the initialization process (i.e. active,
suspended, or canceled)
- the start time for the initialization
- progress is reported via the zpool status command and shows
information for each of the vdevs that are initializing
Porting notes:
- Added zfs_initialize_value module parameter to set the pattern
written by "zpool initialize".
- Added zfs_vdev_{initializing,removal}_{min,max}_active module options.
Authored by: George Wilson <george.wilson@delphix.com>
Reviewed by: John Wren Kennedy <john.kennedy@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: loli10K <ezomori.nozomu@gmail.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Richard Lowe <richlowe@richlowe.net>
Signed-off-by: Tim Chase <tim@chase2k.com>
Ported-by: Tim Chase <tim@chase2k.com>
OpenZFS-issue: https://www.illumos.org/issues/9102
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/c3963210eb
Closes #8230
|
||
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loli10K
|
d48091de81 |
zed: detect and offline physically removed devices
This commit adds a new test case to the ZFS Test Suite to verify ZED can detect when a device is physically removed from a running system: the device will be offlined if a spare is not available in the pool. We implement this by using the existing libudev functionality and without relying solely on the FM kernel module capabilities which have been observed to be unreliable with some kernels. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Don Brady <don.brady@delphix.com> Signed-off-by: loli10K <ezomori.nozomu@gmail.com> Closes #1537 Closes #7926 |
||
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Tom Caputi
|
80a91e7469 |
Defer new resilvers until the current one ends
Currently, if a resilver is triggered for any reason while an existing one is running, zfs will immediately restart the existing resilver from the beginning to include the new drive. This causes problems for system administrators when a drive fails while another is already resilvering. In this case, the optimal thing to do to reduce risk of data loss is to wait for the current resilver to end before immediately replacing the second failed drive, which allows the system to operate with two incomplete drives for the minimum amount of time. This patch introduces the resilver_defer feature that essentially does this for the admin without forcing them to wait and monitor the resilver manually. The change requires an on-disk feature since we must mark drives that are part of a deferred resilver in the vdev config to ensure that we do not assume they are done resilvering when an existing resilver completes. Reviewed-by: Matthew Ahrens <mahrens@delphix.com> Reviewed-by: John Kennedy <john.kennedy@delphix.com> Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: @mmaybee Signed-off-by: Tom Caputi <tcaputi@datto.com> Closes #7732 |
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Allan Jude
|
9f438c5f94 |
OpenZFS 9862 - fix typo in comment in vdev_impl.h
Authored by: Allan Jude <allanjude@freebsd.org> Reviewed by: Matthew Ahrens <mahrens@delphix.com> Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed by: Tony Hutter <hutter2@llnl.gov> Approved by: Robert Mustacchi <rm@joyent.com> Ported-by: George Melikov <mail@gmelikov.ru> OpenZFS-issue: https://www.illumos.org/issues/9862 OpenZFS-commit: https://github.com/openzfs/openzfs/commit/84927f52 Closes #8036 |
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Brian Behlendorf
|
27f80e85c2 |
Improved error handling for extreme rewinds
The vdev_checkpoint_sm_object(), vdev_obsolete_sm_object(), and vdev_obsolete_counts_are_precise() functions assume that the only way a zap_lookup() can fail is if the requested entry is missing. While this is the most common cause, it's not the only cause. Attemping to access a damaged ZAP will result in other errors. The most likely scenario for accessing a damaged ZAP is during an extreme rewind pool import. Under these conditions the pool is expected to contain damaged objects and the import code was updated to handle this gracefully. Getting an ECKSUM error from these ZAPs after the pool in import a far less likely, therefore the behavior for call paths was not modified. Reviewed-by: Tim Chase <tim@chase2k.com> Reviewed-by: Matthew Ahrens <mahrens@delphix.com> Reviewed-by: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Closes #7809 Closes #7921 |
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Don Brady
|
cc99f275a2 |
Pool allocation classes
Allocation Classes add the ability to have allocation classes in a pool that are dedicated to serving specific block categories, such as DDT data, metadata, and small file blocks. A pool can opt-in to this feature by adding a 'special' or 'dedup' top-level VDEV. Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com> Reviewed-by: Richard Laager <rlaager@wiktel.com> Reviewed-by: Alek Pinchuk <apinchuk@datto.com> Reviewed-by: Håkan Johansson <f96hajo@chalmers.se> Reviewed-by: Andreas Dilger <andreas.dilger@chamcloud.com> Reviewed-by: DHE <git@dehacked.net> Reviewed-by: Richard Elling <Richard.Elling@RichardElling.com> Reviewed-by: Gregor Kopka <gregor@kopka.net> Reviewed-by: Kash Pande <kash@tripleback.net> Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Matthew Ahrens <mahrens@delphix.com> Signed-off-by: Don Brady <don.brady@delphix.com> Closes #5182 |
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Paul Dagnelie
|
492f64e941 |
OpenZFS 9112 - Improve allocation performance on high-end systems
Overview ======== We parallelize the allocation process by creating the concept of "allocators". There are a certain number of allocators per metaslab group, defined by the value of a tunable at pool open time. Each allocator for a given metaslab group has up to 2 active metaslabs; one "primary", and one "secondary". The primary and secondary weight mean the same thing they did in in the pre-allocator world; primary metaslabs are used for most allocations, secondary metaslabs are used for ditto blocks being allocated in the same metaslab group. There is also the CLAIM weight, which has been separated out from the other weights, but that is less important to understanding the patch. The active metaslabs for each allocator are moved from their normal place in the metaslab tree for the group to the back of the tree. This way, they will not be selected for use by other allocators searching for new metaslabs unless all the passive metaslabs are unsuitable for allocations. If that does happen, the allocators will "steal" from each other to ensure that IOs don't fail until there is truly no space left to perform allocations. In addition, the alloc queue for each metaslab group has been broken into a separate queue for each allocator. We don't want to dramatically increase the number of inflight IOs on low-end systems, because it can significantly increase txg times. On the other hand, we want to ensure that there are enough IOs for each allocator to allow for good coalescing before sending the IOs to the disk. As a result, we take a compromise path; each allocator's alloc queue max depth starts at a certain value for every txg. Every time an IO completes, we increase the max depth. This should hopefully provide a good balance between the two failure modes, while not dramatically increasing complexity. We also parallelize the spa_alloc_tree and spa_alloc_lock, which cause very similar contention when selecting IOs to allocate. This parallelization uses the same allocator scheme as metaslab selection. Performance Results =================== Performance improvements from this change can vary significantly based on the number of CPUs in the system, whether or not the system has a NUMA architecture, the speed of the drives, the values for the various tunables, and the workload being performed. For an fio async sequential write workload on a 24 core NUMA system with 256 GB of RAM and 8 128 GB SSDs, there is a roughly 25% performance improvement. Future Work =========== Analysis of the performance of the system with this patch applied shows that a significant new bottleneck is the vdev disk queues, which also need to be parallelized. Prototyping of this change has occurred, and there was a performance improvement, but more work needs to be done before its stability has been verified and it is ready to be upstreamed. Authored by: Paul Dagnelie <pcd@delphix.com> Reviewed by: Matthew Ahrens <mahrens@delphix.com> Reviewed by: George Wilson <george.wilson@delphix.com> Reviewed by: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com> Reviewed by: Alexander Motin <mav@FreeBSD.org> Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov> Approved by: Gordon Ross <gwr@nexenta.com> Ported-by: Paul Dagnelie <pcd@delphix.com> Signed-off-by: Paul Dagnelie <pcd@delphix.com> Porting Notes: * Fix reservation test failures by increasing tolerance. OpenZFS-issue: https://illumos.org/issues/9112 OpenZFS-commit: https://github.com/openzfs/openzfs/commit/3f3cc3c3 Closes #7682 |
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Serapheim Dimitropoulos
|
d2734cce68 |
OpenZFS 9166 - zfs storage pool checkpoint
Details about the motivation of this feature and its usage can
be found in this blogpost:
https://sdimitro.github.io/post/zpool-checkpoint/
A lightning talk of this feature can be found here:
https://www.youtube.com/watch?v=fPQA8K40jAM
Implementation details can be found in big block comment of
spa_checkpoint.c
Side-changes that are relevant to this commit but not explained
elsewhere:
* renames members of "struct metaslab trees to be shorter without
losing meaning
* space_map_{alloc,truncate}() accept a block size as a
parameter. The reason is that in the current state all space
maps that we allocate through the DMU use a global tunable
(space_map_blksz) which defauls to 4KB. This is ok for metaslab
space maps in terms of bandwirdth since they are scattered all
over the disk. But for other space maps this default is probably
not what we want. Examples are device removal's vdev_obsolete_sm
or vdev_chedkpoint_sm from this review. Both of these have a
1:1 relationship with each vdev and could benefit from a bigger
block size.
Porting notes:
* The part of dsl_scan_sync() which handles async destroys has
been moved into the new dsl_process_async_destroys() function.
* Remove "VERIFY(!(flags & FWRITE))" in "kernel.c" so zhack can write
to block device backed pools.
* ZTS:
* Fix get_txg() in zpool_sync_001_pos due to "checkpoint_txg".
* Don't use large dd block sizes on /dev/urandom under Linux in
checkpoint_capacity.
* Adopt Delphix-OS's setting of 4 (spa_asize_inflation =
SPA_DVAS_PER_BP + 1) for the checkpoint_capacity test to speed
its attempts to fill the pool
* Create the base and nested pools with sync=disabled to speed up
the "setup" phase.
* Clear labels in test pool between checkpoint tests to avoid
duplicate pool issues.
* The import_rewind_device_replaced test has been marked as "known
to fail" for the reasons listed in its DISCLAIMER.
* New module parameters:
zfs_spa_discard_memory_limit,
zfs_remove_max_bytes_pause (not documented - debugging only)
vdev_max_ms_count (formerly metaslabs_per_vdev)
vdev_min_ms_count
Authored by: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: John Kennedy <john.kennedy@delphix.com>
Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Richard Lowe <richlowe@richlowe.net>
Ported-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Tim Chase <tim@chase2k.com>
OpenZFS-issue: https://illumos.org/issues/9166
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/7159fdb8
Closes #7570
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Pavel Zakharov
|
6cb8e5306d |
OpenZFS 9075 - Improve ZFS pool import/load process and corrupted pool recovery
Some work has been done lately to improve the debugability of the ZFS pool load (and import) process. This includes: 7638 Refactor spa_load_impl into several functions 8961 SPA load/import should tell us why it failed 7277 zdb should be able to print zfs_dbgmsg's To iterate on top of that, there's a few changes that were made to make the import process more resilient and crash free. One of the first tasks during the pool load process is to parse a config provided from userland that describes what devices the pool is composed of. A vdev tree is generated from that config, and then all the vdevs are opened. The Meta Object Set (MOS) of the pool is accessed, and several metadata objects that are necessary to load the pool are read. The exact configuration of the pool is also stored inside the MOS. Since the configuration provided from userland is external and might not accurately describe the vdev tree of the pool at the txg that is being loaded, it cannot be relied upon to safely operate the pool. For that reason, the configuration in the MOS is read early on. In the past, the two configurations were compared together and if there was a mismatch then the load process was aborted and an error was returned. The latter was a good way to ensure a pool does not get corrupted, however it made the pool load process needlessly fragile in cases where the vdev configuration changed or the userland configuration was outdated. Since the MOS is stored in 3 copies, the configuration provided by userland doesn't have to be perfect in order to read its contents. Hence, a new approach has been adopted: The pool is first opened with the untrusted userland configuration just so that the real configuration can be read from the MOS. The trusted MOS configuration is then used to generate a new vdev tree and the pool is re-opened. When the pool is opened with an untrusted configuration, writes are disabled to avoid accidentally damaging it. During reads, some sanity checks are performed on block pointers to see if each DVA points to a known vdev; when the configuration is untrusted, instead of panicking the system if those checks fail we simply avoid issuing reads to the invalid DVAs. This new two-step pool load process now allows rewinding pools accross vdev tree changes such as device replacement, addition, etc. Loading a pool from an external config file in a clustering environment also becomes much safer now since the pool will import even if the config is outdated and didn't, for instance, register a recent device addition. With this code in place, it became relatively easy to implement a long-sought-after feature: the ability to import a pool with missing top level (i.e. non-redundant) devices. Note that since this almost guarantees some loss of data, this feature is for now restricted to a read-only import. Porting notes (ZTS): * Fix 'make dist' target in zpool_import * The maximum path length allowed by tar is 99 characters. Several of the new test cases exceeded this limit resulting in them not being included in the tarball. Shorten the names slightly. * Set/get tunables using accessor functions. * Get last synced txg via the "zfs_txg_history" mechanism. * Clear zinject handlers in cleanup for import_cache_device_replaced and import_rewind_device_replaced in order that the zpool can be exported if there is an error. * Increase FILESIZE to 8G in zfs-test.sh to allow for a larger ext4 file system to be created on ZFS_DISK2. Also, there's no need to partition ZFS_DISK2 at all. The partitioning had already been disabled for multipath devices. Among other things, the partitioning steals some space from the ext4 file system, makes it difficult to accurately calculate the paramters to parted and can make some of the tests fail. * Increase FS_SIZE and FILE_SIZE in the zpool_import test configuration now that FILESIZE is larger. * Write more data in order that device evacuation take lonnger in a couple tests. * Use mkdir -p to avoid errors when the directory already exists. * Remove use of sudo in import_rewind_config_changed. Authored by: Pavel Zakharov <pavel.zakharov@delphix.com> Reviewed by: George Wilson <george.wilson@delphix.com> Reviewed by: Matthew Ahrens <mahrens@delphix.com> Reviewed by: Andrew Stormont <andyjstormont@gmail.com> Approved by: Hans Rosenfeld <rosenfeld@grumpf.hope-2000.org> Ported-by: Tim Chase <tim@chase2k.com> Signed-off-by: Tim Chase <tim@chase2k.com> OpenZFS-issue: https://illumos.org/issues/9075 OpenZFS-commit: https://github.com/openzfs/openzfs/commit/619c0123 Closes #7459 |
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Matthew Ahrens
|
a1d477c24c |
OpenZFS 7614, 9064 - zfs device evacuation/removal
OpenZFS 7614 - zfs device evacuation/removal
OpenZFS 9064 - remove_mirror should wait for device removal to complete
This project allows top-level vdevs to be removed from the storage pool
with "zpool remove", reducing the total amount of storage in the pool.
This operation copies all allocated regions of the device to be removed
onto other devices, recording the mapping from old to new location.
After the removal is complete, read and free operations to the removed
(now "indirect") vdev must be remapped and performed at the new location
on disk. The indirect mapping table is kept in memory whenever the pool
is loaded, so there is minimal performance overhead when doing operations
on the indirect vdev.
The size of the in-memory mapping table will be reduced when its entries
become "obsolete" because they are no longer used by any block pointers
in the pool. An entry becomes obsolete when all the blocks that use
it are freed. An entry can also become obsolete when all the snapshots
that reference it are deleted, and the block pointers that reference it
have been "remapped" in all filesystems/zvols (and clones). Whenever an
indirect block is written, all the block pointers in it will be "remapped"
to their new (concrete) locations if possible. This process can be
accelerated by using the "zfs remap" command to proactively rewrite all
indirect blocks that reference indirect (removed) vdevs.
Note that when a device is removed, we do not verify the checksum of
the data that is copied. This makes the process much faster, but if it
were used on redundant vdevs (i.e. mirror or raidz vdevs), it would be
possible to copy the wrong data, when we have the correct data on e.g.
the other side of the mirror.
At the moment, only mirrors and simple top-level vdevs can be removed
and no removal is allowed if any of the top-level vdevs are raidz.
Porting Notes:
* Avoid zero-sized kmem_alloc() in vdev_compact_children().
The device evacuation code adds a dependency that
vdev_compact_children() be able to properly empty the vdev_child
array by setting it to NULL and zeroing vdev_children. Under Linux,
kmem_alloc() and related functions return a sentinel pointer rather
than NULL for zero-sized allocations.
* Remove comment regarding "mpt" driver where zfs_remove_max_segment
is initialized to SPA_MAXBLOCKSIZE.
Change zfs_condense_indirect_commit_entry_delay_ticks to
zfs_condense_indirect_commit_entry_delay_ms for consistency with
most other tunables in which delays are specified in ms.
* ZTS changes:
Use set_tunable rather than mdb
Use zpool sync as appropriate
Use sync_pool instead of sync
Kill jobs during test_removal_with_operation to allow unmount/export
Don't add non-disk names such as "mirror" or "raidz" to $DISKS
Use $TEST_BASE_DIR instead of /tmp
Increase HZ from 100 to 1000 which is more common on Linux
removal_multiple_indirection.ksh
Reduce iterations in order to not time out on the code
coverage builders.
removal_resume_export:
Functionally, the test case is correct but there exists a race
where the kernel thread hasn't been fully started yet and is
not visible. Wait for up to 1 second for the removal thread
to be started before giving up on it. Also, increase the
amount of data copied in order that the removal not finish
before the export has a chance to fail.
* MMP compatibility, the concept of concrete versus non-concrete devices
has slightly changed the semantics of vdev_writeable(). Update
mmp_random_leaf_impl() accordingly.
* Updated dbuf_remap() to handle the org.zfsonlinux:large_dnode pool
feature which is not supported by OpenZFS.
* Added support for new vdev removal tracepoints.
* Test cases removal_with_zdb and removal_condense_export have been
intentionally disabled. When run manually they pass as intended,
but when running in the automated test environment they produce
unreliable results on the latest Fedora release.
They may work better once the upstream pool import refectoring is
merged into ZoL at which point they will be re-enabled.
Authored by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Alex Reece <alex@delphix.com>
Reviewed-by: George Wilson <george.wilson@delphix.com>
Reviewed-by: John Kennedy <john.kennedy@delphix.com>
Reviewed-by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: Richard Laager <rlaager@wiktel.com>
Reviewed by: Tim Chase <tim@chase2k.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Garrett D'Amore <garrett@damore.org>
Ported-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Tim Chase <tim@chase2k.com>
OpenZFS-issue: https://www.illumos.org/issues/7614
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/f539f1eb
Closes #6900
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||
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Tony Hutter
|
80d52c3919 |
Change checksum & IO delay ratelimit values
Change checksum & IO delay ratelimit thresholds from 5/sec to 20/sec. This allows zed to actually trigger if a bunch of these events arrive in a short period of time (zed has a threshold of 10 events in 10 sec). Previously, if you had, say, 100 checksum errors in 1 sec, it would get ratelimited to 5/sec which wouldn't trigger zed to fault the drive. Also, convert the checksum and IO delay thresholds to module params for easy testing. Reviewed-by: loli10K <ezomori.nozomu@gmail.com> Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov> Signed-off-by: Tony Hutter <hutter2@llnl.gov> Closes #7252 |
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Olaf Faaland
|
7088545d01 |
Report duration and error in mmp_history entries
After an MMP write completes, update the relevant mmp_history entry with the time between submission and completion, and the error status of the write. [faaland1@toss3a zfs]$ cat /proc/spl/kstat/zfs/pool/multihost 39 0 0x01 100 8800 69147946270893 72723903122926 id txg timestamp error duration mmp_delay vdev_guid 10607 1166 1518985089 0 138301 637785455 4882... 10608 1166 1518985089 0 136154 635407747 1151... 10609 1166 1518985089 0 803618560 633048078 9740... 10610 1166 1518985090 0 144826 633048078 4882... 10611 1166 1518985090 0 164527 666187671 1151... Where duration = gethrtime_in_done_fn - gethrtime_at_submission, and error = zio->io_error. Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov> Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Olaf Faaland <faaland1@llnl.gov> Closes #7190 |
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Tom Caputi
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d4a72f2386 |
Sequential scrub and resilvers
Currently, scrubs and resilvers can take an extremely long time to complete. This is largely due to the fact that zfs scans process pools in logical order, as determined by each block's bookmark. This makes sense from a simplicity perspective, but blocks in zfs are often scattered randomly across disks, particularly due to zfs's copy-on-write mechanisms. This patch improves performance by splitting scrubs and resilvers into a metadata scanning phase and an IO issuing phase. The metadata scan reads through the structure of the pool and gathers an in-memory queue of I/Os, sorted by size and offset on disk. The issuing phase will then issue the scrub I/Os as sequentially as possible, greatly improving performance. This patch also updates and cleans up some of the scan code which has not been updated in several years. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Authored-by: Saso Kiselkov <saso.kiselkov@nexenta.com> Authored-by: Alek Pinchuk <apinchuk@datto.com> Authored-by: Tom Caputi <tcaputi@datto.com> Signed-off-by: Tom Caputi <tcaputi@datto.com> Closes #3625 Closes #6256 |
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Gvozden Neskovic
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d6c6590c5d |
vdev_mirror: load balancing fixes
vdev_queue: - Track the last position of each vdev, including the io size, in order to detect linear access of the following zio. - Remove duplicate `vq_lastoffset` vdev_mirror: - Correctly calculate the zio offset (signedness issue) - Deprecate `vdev_queue_register_lastoffset()` - Add `VDEV_LABEL_START_SIZE` to zio offset of leaf vdevs Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Gvozden Neskovic <neskovic@gmail.com> Closes #6461 |