Traditional dedup keeps a separate ddt_phys_t "type" for each possible
count of DVAs (that is, copies=) parameter. Each of these are tracked
independently of each other, and have their own set of DVAs. This leads
to an (admittedly rare) situation where you can create as many as six
copies of the data, by changing the copies= parameter between copying.
This is both a waste of storage on disk, but also a waste of space in
the stored DDT entries, since there never needs to be more than three
DVAs to handle all possible values of copies=.
This commit adds a new FDT feature, DDT_FLAG_FLAT. When active, only the
first ddt_phys_t is used. Each time a block is written with the dedup
bit set, this single phys is checked to see if it has enough DVAs to
fulfill the request. If it does, the block is filled with the saved DVAs
as normal. If not, an adjusted write is issued to create as many extra
copies as are needed to fulfill the request, which are then saved into
the entry too.
Because a single phys is no longer an all-or-nothing, but can be
transitioning from fewer to more DVAs, the write path now has to keep a
copy of the previous "known good" DVA set so we can revert to it in case
an error occurs. zio_ddt_write() has been restructured and heavily
commented to make it much easier to see what's happening.
Backwards compatibility is maintained simply by allocating four
ddt_phys_t when the DDT_FLAG_FLAT flag is not set, and updating the phys
selection macros to check the flag. In the old arrangement, each number
of copies gets a whole phys, so it will always have either zero or all
necessary DVAs filled, with no in-between, so the old behaviour
naturally falls out of the new code.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Co-authored-by: Don Brady <don.brady@klarasystems.com>
Sponsored-by: Klara, Inc.
Sponsored-by: iXsystems, Inc.
Closes#15893
The "flat phys" feature will use only a single phys slot for all
entries, which means the old "single", "double" etc naming now makes no
sense, and more importantly, means that choosing the right slot for a
given block pointer will depend on how many slots are in use for a given
DDT.
This removes the old names, and adds accessor macros to decouple
specific phys array indexes from any particular meaning.
(These macros look strange in isolation, mainly in the way they take the
ddt_t* as an arg but don't use it. This is mostly a separate commit to
introduce the concept to the reader before the "flat phys" commit
extends it).
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-by: Klara, Inc.
Sponsored-by: iXsystems, Inc.
Closes#15893
This change adds a new `zpool prefetch -t ddt $pool` command which
causes a pool's DDT to be loaded into the ARC. The primary goal is to
remove the need to "warm" a pool's cache before deduplication stops
slowing write performance. It may also provide a way to reload portions
of a DDT if they have been flushed due to inactivity.
Sponsored-by: iXsystems, Inc.
Sponsored-by: Catalogics, Inc.
Sponsored-by: Klara, Inc.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Allan Jude <allan@klarasystems.com>
Signed-off-by: Will Andrews <will.andrews@klarasystems.com>
Signed-off-by: Fred Weigel <fred.weigel@klarasystems.com>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Signed-off-by: Don Brady <don.brady@klarasystems.com>
Co-authored-by: Will Andrews <will.andrews@klarasystems.com>
Co-authored-by: Don Brady <don.brady@klarasystems.com>
Closes#15890
Store objects store keys and values, so have them take those types and
nothing more. This way, they don't need to be concerned about the "kind"
of entry being operated on; the dispatch layer can take care of the
appropriate conversions.
This adds a "contains" op to see if a particular entry exists without
loading it, which makes a couple of things easier to do; in particular,
it allows us to avoid an allocation in ddt_class_contains().
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-by: Klara, Inc.
Sponsored-by: iXsystems, Inc.
Closes#15887
Just to make it easier to know which bits to pay attention to.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-by: Klara, Inc.
Sponsored-by: iXsystems, Inc.
Closes#15887
Always do them on the heap, and when we know how much we need, only that
much.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-by: Klara, Inc.
Sponsored-by: iXsystems, Inc.
Closes#15887
I think I can say with some confidence that anyone making a new storage
type in 2023 is doing their own thing with compression, not this.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-by: Klara, Inc.
Sponsored-by: iXsystems, Inc.
Closes#15887
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-by: Klara, Inc.
Sponsored-by: iXsystems, Inc.
Closes#15887
The DDT is really inefficient on 4k and up vdevs, because it always
allocates 4k blocks, and while compression could save us somewhat
at ashift 9, that stops being true.
So let's change the default to 32 KiB, which seems like a reasonable
compromise between improved space savings and inflated write sizes
for DDT updates.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rich Ercolani <rincebrain@gmail.com>
Closes#14654
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
* Add dedicated donde_set_dirtyctx routine.
* Add empty dirty record on destroy assertion.
* Make much more extensive use of the SET_ERROR macro.
Reviewed-by: Will Andrews <wca@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes#9924
When iterating over a ZAP object, we're almost always certain to iterate
over the entire object. If there are multiple leaf blocks, we can
realize a performance win by issuing reads for all the leaf blocks in
parallel when the iteration begins.
For example, if we have 10,000 snapshots, "zfs destroy -nv
pool/fs@1%9999" can take 30 minutes when the cache is cold. This change
provides a >3x performance improvement, by issuing the reads for all ~64
blocks of each ZAP object in parallel.
Reviewed-by: Andreas Dilger <andreas.dilger@whamcloud.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
External-issue: DLPX-58347
Closes#8862
Minimal changes required to integrate the SPL sources in to the
ZFS repository build infrastructure and packaging.
Build system and packaging:
* Renamed SPL_* autoconf m4 macros to ZFS_*.
* Removed redundant SPL_* autoconf m4 macros.
* Updated the RPM spec files to remove SPL package dependency.
* The zfs package obsoletes the spl package, and the zfs-kmod
package obsoletes the spl-kmod package.
* The zfs-kmod-devel* packages were updated to add compatibility
symlinks under /usr/src/spl-x.y.z until all dependent packages
can be updated. They will be removed in a future release.
* Updated copy-builtin script for in-kernel builds.
* Updated DKMS package to include the spl.ko.
* Updated stale AUTHORS file to include all contributors.
* Updated stale COPYRIGHT and included the SPL as an exception.
* Renamed README.markdown to README.md
* Renamed OPENSOLARIS.LICENSE to LICENSE.
* Renamed DISCLAIMER to NOTICE.
Required code changes:
* Removed redundant HAVE_SPL macro.
* Removed _BOOT from nvpairs since it doesn't apply for Linux.
* Initial header cleanup (removal of empty headers, refactoring).
* Remove SPL repository clone/build from zimport.sh.
* Use of DEFINE_RATELIMIT_STATE and DEFINE_SPINLOCK removed due
to build issues when forcing C99 compilation.
* Replaced legacy ACCESS_ONCE with READ_ONCE.
* Include needed headers for `current` and `EXPORT_SYMBOL`.
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Olaf Faaland <faaland1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Pavel Zakharov <pavel.zakharov@delphix.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
TEST_ZIMPORT_SKIP="yes"
Closes#7556
By marking DMU transaction processing contexts with PF_FSTRANS
we can revert the KM_PUSHPAGE -> KM_SLEEP changes. This brings
us back in line with upstream. In some cases this means simply
swapping the flags back. For others fnvlist_alloc() was replaced
by nvlist_alloc(..., KM_PUSHPAGE) and must be reverted back to
fnvlist_alloc() which assumes KM_SLEEP.
The one place KM_PUSHPAGE is kept is when allocating ARC buffers
which allows us to dip in to reserved memory. This is again the
same as upstream.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
The vast majority of these changes are in Linux specific code.
They are the result of not having an automated style checker to
validate the code when it was originally written. Others were
caused when the common code was slightly adjusted for Linux.
This patch contains no functional changes. It only refreshes
the code to conform to style guide.
Everyone submitting patches for inclusion upstream should now
run 'make checkstyle' and resolve any warning prior to opening
a pull request. The automated builders have been updated to
fail a build if when 'make checkstyle' detects an issue.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1821
The interface for the ddt_zap_count() function assumes it can
never fail. However, internally ddt_zap_count() is implemented
with zap_count() which can potentially fail. Now because there
was no way to return the error to the caller a VERIFY was used
to ensure this case never happens.
Unfortunately, it has been observed that pools can be damaged in
such a way that zap_count() fails. The result is that the pool can
not be imported without hitting the VERIFY and crashing the system.
This patch reworks ddt_object_count() so the error can be safely
caught and returned to the caller. This allows a pool which has
be damaged in this way to be safely rewound for import.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#910
This warning indicates the incorrect use of KM_SLEEP in a call
path which must use KM_PUSHPAGE to avoid deadlocking in direct
reclaim. See commit b8d06fc for additional details.
SPL: Fixing allocation for task txg_sync (6093) which
used GFP flags 0x297bda7c with PF_NOFS set
Signed-off-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1002
When the ddt_zap_lookup() function was updated to dynamically
allocate memory for the cbuf variable, to save stack space, the
'csize <= sizeof (cbuf)' assertion was not updated. The result
of this was that the size of the pointer was being used in the
comparison rather than the buffer size.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Stack usage for ddt_zap_lookup() reduced from 368 bytes to 120
bytes. This large stack allocation significantly contributed to
the likelyhood of a stack overflow when scrubbing/resilvering
dedup pools.
