mirror_zfs/include/sys/vdev_rebuild.h
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
2020-11-13 13:51:51 -08:00

102 lines
3.4 KiB
C

/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2018, Intel Corporation.
* Copyright (c) 2020 by Lawrence Livermore National Security, LLC.
*/
#ifndef _SYS_VDEV_REBUILD_H
#define _SYS_VDEV_REBUILD_H
#include <sys/spa.h>
#ifdef __cplusplus
extern "C" {
#endif
/*
* Number of entries in the physical vdev_rebuild_phys structure. This
* state is stored per top-level as VDEV_ZAP_TOP_VDEV_REBUILD_PHYS.
*/
#define REBUILD_PHYS_ENTRIES 12
/*
* On-disk rebuild configuration and state. When adding new fields they
* must be added to the end of the structure.
*/
typedef struct vdev_rebuild_phys {
uint64_t vrp_rebuild_state; /* vdev_rebuild_state_t */
uint64_t vrp_last_offset; /* last rebuilt offset */
uint64_t vrp_min_txg; /* minimum missing txg */
uint64_t vrp_max_txg; /* maximum missing txg */
uint64_t vrp_start_time; /* start time */
uint64_t vrp_end_time; /* end time */
uint64_t vrp_scan_time_ms; /* total run time in ms */
uint64_t vrp_bytes_scanned; /* alloc bytes scanned */
uint64_t vrp_bytes_issued; /* read bytes rebuilt */
uint64_t vrp_bytes_rebuilt; /* rebuilt bytes */
uint64_t vrp_bytes_est; /* total bytes to scan */
uint64_t vrp_errors; /* errors during rebuild */
} vdev_rebuild_phys_t;
/*
* The vdev_rebuild_t describes the current state and how a top-level vdev
* should be rebuilt. The core elements are the top-vdev, the metaslab being
* rebuilt, range tree containing the allocted extents and the on-disk state.
*/
typedef struct vdev_rebuild {
vdev_t *vr_top_vdev; /* top-level vdev to rebuild */
metaslab_t *vr_scan_msp; /* scanning disabled metaslab */
range_tree_t *vr_scan_tree; /* scan ranges (in metaslab) */
kmutex_t vr_io_lock; /* inflight IO lock */
kcondvar_t vr_io_cv; /* inflight IO cv */
/* In-core state and progress */
uint64_t vr_scan_offset[TXG_SIZE];
uint64_t vr_prev_scan_time_ms; /* any previous scan time */
uint64_t vr_bytes_inflight_max; /* maximum bytes inflight */
uint64_t vr_bytes_inflight; /* current bytes inflight */
/* Per-rebuild pass statistics for calculating bandwidth */
uint64_t vr_pass_start_time;
uint64_t vr_pass_bytes_scanned;
uint64_t vr_pass_bytes_issued;
/* On-disk state updated by vdev_rebuild_zap_update_sync() */
vdev_rebuild_phys_t vr_rebuild_phys;
} vdev_rebuild_t;
boolean_t vdev_rebuild_active(vdev_t *);
int vdev_rebuild_load(vdev_t *);
void vdev_rebuild(vdev_t *);
void vdev_rebuild_stop_wait(vdev_t *);
void vdev_rebuild_stop_all(spa_t *);
void vdev_rebuild_restart(spa_t *);
void vdev_rebuild_clear_sync(void *, dmu_tx_t *);
int vdev_rebuild_get_stats(vdev_t *, vdev_rebuild_stat_t *);
#ifdef __cplusplus
}
#endif
#endif /* _SYS_VDEV_REBUILD_H */