Re: (subset) [PATCH 22/32] vfs: inode cache conversion to hash-bl

From: Christian Brauner
Date: Tue May 23 2023 - 05:28:51 EST


On Tue, 09 May 2023 12:56:47 -0400, Kent Overstreet wrote:
> Because scalability of the global inode_hash_lock really, really
> sucks.
>
> 32-way concurrent create on a couple of different filesystems
> before:
>
> - 52.13% 0.04% [kernel] [k] ext4_create
> - 52.09% ext4_create
> - 41.03% __ext4_new_inode
> - 29.92% insert_inode_locked
> - 25.35% _raw_spin_lock
> - do_raw_spin_lock
> - 24.97% __pv_queued_spin_lock_slowpath
>
> [...]

This is interesting completely independent of bcachefs so we should give
it some testing.

I updated a few places that had outdated comments.

---

Applied to the vfs.unstable.inode-hash branch of the vfs/vfs.git tree.
Patches in the vfs.unstable.inode-hash branch should appear in linux-next soon.

Please report any outstanding bugs that were missed during review in a
new review to the original patch series allowing us to drop it.

It's encouraged to provide Acked-bys and Reviewed-bys even though the
patch has now been applied. If possible patch trailers will be updated.

tree: https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
branch: vfs.unstable.inode-hash

[22/32] vfs: inode cache conversion to hash-bl
https://git.kernel.org/vfs/vfs/c/e3e92d47e6b1