On 8/5/25 14:52, Daniel Lee wrote:
> For casefolded directories, f2fs may fall back to a linear search if
> a hash-based lookup fails. This can cause severe performance
> regressions.
> 
> While this behavior can be controlled by userspace tools (e.g. mkfs,
> fsck) by setting an on-disk flag, a kernel-level solution is needed
> to guarantee the lookup behavior regardless of the on-disk state.
> 
> This commit introduces the 'lookup_mode' mount option to provide this
> kernel-side control.
> 
> The option accepts three values:
> - perf: (Default) Enforces a hash-only lookup. The linear fallback
>   is always disabled.
> - compat: Enables the linear search fallback for compatibility with
>   directory entries from older kernels.
> - auto: Determines the mode based on the on-disk flag, preserving the
>   userspace-based behavior.
> 
> Signed-off-by: Daniel Lee <[email protected]>

Reviewed-by: Chao Yu <[email protected]>

Thanks,


_______________________________________________
Linux-f2fs-devel mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

Reply via email to