Re: [PATCH v2 00/16] Parallelizing filesystem writeback

Kundan Kumar
2025-10-15T08:55:11Z

>
> Nice results. Is testing planned for other filesystems?
>

The changes currently improve the writeback performance for XFS only.
We have introduced a callback that other filesystems can implement to
decide which writeback context an inode should be affined to.

This is because the decision to affine an inode to a particular
writeback context depends on the FS geometry. For example, in XFS
inodes belonging to the same allocation group should be affined to the
same writeback context. Arbitrarily distributing inodes across
different writeback contexts can lead to contention of FS resources,
which can degrade performance.

I conducted a sanity check on the performance of EXT4, BTRFS, and F2FS
with the current changes, and the results show no performance impact.