Updates of the raid-stripe-tree are done at ordered extent write time to safe
on bandwidth while for reading we do the stripe-tree lookup on bio mapping
time, i.e. when the logical to physical translation happens for regular btrfs
RAID as well.
The stripe tree is keyed by an extent's disk_bytenr and disk_num_bytes and
it's contents are the respective physical device id and position.
For an example 1M write (split into 126K segments due to zone-append)
rapido2:/home/johannes/src/fstests# xfs_io -fdc "pwrite -b 1M 0 1M" -c fsync /mnt/test/test
wrote 1048576/1048576 bytes at offset 0
1 MiB, 1 ops; 0.0065 sec (151.538 MiB/sec and 151.5381 ops/sec)
The tree will look as follows (both 128k buffered writes to a ZNS drive):
RAID0 case:
bash-5.2# btrfs inspect-internal dump-tree -t raid_stripe /dev/nvme0n1
btrfs-progs v6.3
raid stripe tree key (RAID_STRIPE_TREE ROOT_ITEM 0)
leaf 805535744 items 1 free space 16218 generation 8 owner RAID_STRIPE_TREE
leaf 805535744 flags 0x1(WRITTEN) backref revision 1
checksum stored 2d2d2262
checksum calced 2d2d2262
fs uuid ab05cfc6-9859-404e-970d-3999b1cb5438
chunk uuid c9470ba2-49ac-4d46-8856-438a18e6bd23
item 0 key (1073741824 RAID_STRIPE_KEY 131072) itemoff 16243 itemsize 40
encoding: RAID0
stripe 0 devid 1 offset 805306368
stripe 1 devid 2 offset 536870912
total bytes 42949672960
bytes used 294912
uuid ab05cfc6-9859-404e-970d-3999b1cb5438
RAID1 case:
bash-5.2# btrfs inspect-internal dump-tree -t raid_stripe /dev/nvme0n1
btrfs-progs v6.3
raid stripe tree key (RAID_STRIPE_TREE ROOT_ITEM 0)
leaf 805535744 items 1 free space 16218 generation 8 owner RAID_STRIPE_TREE
leaf 805535744 flags 0x1(WRITTEN) backref revision 1
checksum stored 56199539
checksum calced 56199539
fs uuid 9e693a37-fbd1-4891-aed2-e7fe64605045
chunk uuid 691874fc-1b9c-469b-bd7f-05e0e6ba88c4
item 0 key (939524096 RAID_STRIPE_KEY 131072) itemoff 16243 itemsize 40
encoding: RAID1
stripe 0 devid 1 offset 939524096
stripe 1 devid 2 offset 536870912
total bytes 42949672960
bytes used 294912
uuid 9e693a37-fbd1-4891-aed2-e7fe64605045
A design document can be found here:
https://docs.google.com/document/d/1Iui_jMidCd4MVBNSSLXRfO7p5KmvnoQL/edit?usp=sharing&ouid=103609947580185458266&rtpof=true&sd=true
The user-space part of this series can be found here:
https://lore.kernel.org/linux-btrfs/[email protected]
Changes to v7:
- Huge rewrite
v7 of the patchset can be found here:
https://lore.kernel.org/linux-btrfs/[email protected]/
Changes to v6:
- Fix degraded RAID1 mounts
- Fix RAID0/10 mounts
v6 of the patchset can be found here:
https://lore/kernel.org/linux-btrfs/[email protected]
Changes to v5:
- Incroporated review comments from Josef and Christoph
- Rebased onto misc-next
v5 of the patchset can be found here:
https://lore/kernel.org/linux-btrfs/[email protected]
Changes to v4:
- Added patch to check for RST feature in sysfs
- Added RST lookups for scrubbing
- Fixed the error handling bug Josef pointed out
- Only check if we need to write out a RST once per delayed_ref head
- Added support for zoned data DUP with RST
Changes to v3:
- Rebased onto [email protected]
- Incorporated Josef's review
- Merged related patches
v3 of the patchset can be found here:
https://lore/kernel.org/linux-btrfs/[email protected]
Changes to v2:
- Bug fixes
- Rebased onto [email protected]
- Added tracepoints
- Added leak checker
- Added RAID0 and RAID10
v2 of the patchset can be found here:
https://lore.kernel.org/linux-btrfs/[email protected]
Changes to v1:
- Write the stripe-tree at delayed-ref time (Qu)
- Add a different write path for preallocation
v1 of the patchset can be found here:
https://lore.kernel.org/linux-btrfs/[email protected]/
Signed-off-by: Johannes Thumshirn <[email protected]>
---
Johannes Thumshirn (11):
btrfs: add raid stripe tree definitions
btrfs: read raid-stripe-tree from disk
btrfs: add support for inserting raid stripe extents
btrfs: delete stripe extent on extent deletion
btrfs: lookup physical address from stripe extent
btrfs: implement RST version of scrub
btrfs: zoned: allow zoned RAID
btrfs: add raid stripe tree pretty printer
btrfs: announce presence of raid-stripe-tree in sysfs
btrfs: add trace events for RST
btrfs: add raid-stripe-tree to features enabled with debug
fs/btrfs/Makefile | 2 +-
fs/btrfs/accessors.h | 10 +
fs/btrfs/bio.c | 23 ++
fs/btrfs/block-rsv.c | 6 +
fs/btrfs/disk-io.c | 18 ++
fs/btrfs/disk-io.h | 5 +
fs/btrfs/extent-tree.c | 7 +
fs/btrfs/fs.h | 4 +-
fs/btrfs/inode.c | 8 +-
fs/btrfs/locking.c | 5 +-
fs/btrfs/ordered-data.c | 1 +
fs/btrfs/ordered-data.h | 2 +
fs/btrfs/print-tree.c | 49 ++++
fs/btrfs/raid-stripe-tree.c | 493 ++++++++++++++++++++++++++++++++++++++++
fs/btrfs/raid-stripe-tree.h | 52 +++++
fs/btrfs/scrub.c | 56 +++++
fs/btrfs/sysfs.c | 3 +
fs/btrfs/volumes.c | 43 +++-
fs/btrfs/volumes.h | 15 +-
fs/btrfs/zoned.c | 113 ++++++++-
include/trace/events/btrfs.h | 75 ++++++
include/uapi/linux/btrfs.h | 1 +
include/uapi/linux/btrfs_tree.h | 33 ++-
23 files changed, 999 insertions(+), 25 deletions(-)
---
base-commit: 133da717263112d81bb95b5535ceb2c1eeddd4e7
change-id: 20230613-raid-stripe-tree-e330c9a45cc3
Best regards,
--
Johannes Thumshirn <[email protected]>