freebsd-nq/module/zcommon
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
..
cityhash.c Compile cityhash code into libzfs 2020-03-27 09:11:22 -07:00
Makefile.in Cleanup linux module kbuild files 2020-06-10 09:24:15 -07:00
zfeature_common.c Distributed Spare (dRAID) Feature 2020-11-13 13:51:51 -08:00
zfs_comutil.c Fix "zpool add -n" for dedup, special and log devices 2020-01-06 15:40:06 -08:00
zfs_deleg.c Remove code for zfs remap 2019-06-24 16:44:01 -07:00
zfs_fletcher_aarch64_neon.c OpenZFS restructuring - move platform specific headers 2019-09-05 09:34:54 -07:00
zfs_fletcher_avx512.c Refactor ccompile.h to not include system headers 2020-07-25 20:09:50 -07:00
zfs_fletcher_intel.c OpenZFS restructuring - move platform specific headers 2019-09-05 09:34:54 -07:00
zfs_fletcher_sse.c OpenZFS restructuring - move platform specific headers 2019-09-05 09:34:54 -07:00
zfs_fletcher_superscalar4.c Refactor ccompile.h to not include system headers 2020-07-25 20:09:50 -07:00
zfs_fletcher_superscalar.c Refactor ccompile.h to not include system headers 2020-07-25 20:09:50 -07:00
zfs_fletcher.c FreeBSD: disable neon usage 2020-08-26 09:54:37 -07:00
zfs_namecheck.c Distributed Spare (dRAID) Feature 2020-11-13 13:51:51 -08:00
zfs_prop.c Update references to nonexistent man pages in code 2020-10-30 08:55:59 -07:00
zfs_uio.c Bugfix/fix uio partial copies 2020-04-01 09:48:54 -07:00
zpool_prop.c Add define to enable autotrim to default to on 2020-08-18 09:52:30 -07:00
zprop_common.c Left-align index props 2020-01-31 08:55:51 -08:00