diff options
| author |   Naohiro Aota <naohiro.aota@wdc.com> | 2021-02-04 19:22:10 +0900 |
|---|---|---|
| committer |   David Sterba <dsterba@suse.com> | 2021-02-09 02:46:07 +0100 |
| commit | 4eef29ef6360d9c3e4be111392e20b70e19171cc (patch) | |
| tree | e30793e811042b270e3b75af4078b7130aaa160c /fs/btrfs | |
| parent | btrfs: zoned: wait for existing extents before truncating (diff) | |
| download | linux-dev-4eef29ef6360d9c3e4be111392e20b70e19171cc.tar.xz linux-dev-4eef29ef6360d9c3e4be111392e20b70e19171cc.zip | |
btrfs: zoned: do not use async metadata checksum on zoned filesystems
On zoned filesystems, btrfs uses per-fs zoned_meta_io_lock to serialize
the metadata write IOs.
Even with this serialization, write bios sent from btree_write_cache_pages
can be reordered by async checksum workers as these workers are per CPU
and not per zone.
To preserve write bio ordering, we disable async metadata checksum on a
zoned filesystem. This does not result in lower performance with HDDs as
a single CPU core is fast enough to do checksum for a single zone write
stream with the maximum possible bandwidth of the device. If multiple
zones are being written simultaneously, HDD seek overhead lowers the
achievable maximum bandwidth, resulting again in a per zone checksum
serialization not affecting the performance.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs')
| -rw-r--r-- | fs/btrfs/disk-io.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 458bb27e0327..6e16f556ed75 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -871,6 +871,8 @@ static blk_status_t btree_submit_bio_start(struct inode *inode, struct bio *bio, static int check_async_write(struct btrfs_fs_info *fs_info, struct btrfs_inode *bi) { + if (btrfs_is_zoned(fs_info)) + return 0; if (atomic_read(&bi->sync_writers)) return 0; if (test_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags)) |