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	Fri, 10 Jan 2025 16:24:57 +0000
Date: Fri, 10 Jan 2025 16:24:57 +0000
From: Al Viro <viro@zeniv.linux.org.uk>
To: Jan Kara <jack@suse.cz>
Cc: linux-fsdevel@vger.kernel.org, agruenba@redhat.com, amir73il@gmail.com,
	brauner@kernel.org, ceph-devel@vger.kernel.org, dhowells@redhat.com,
	hubcap@omnibond.com, krisman@kernel.org, linux-nfs@vger.kernel.org,
	miklos@szeredi.hu, torvalds@linux-foundation.org
Subject: Re: [PATCH 02/20] dcache: back inline names with a struct-wrapped
 array of unsigned long
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Fri, Jan 10, 2025 at 10:35:14AM +0100, Jan Kara wrote:

> I was thinking for a while whether if you now always copy 40 bytes instead
> of only d_name.len bytes cannot have any adverse performance effects
> (additional cacheline fetched / dirtied) but I don't think any path copying
> the name is that performance critical to matter if it would be noticeable
> at all.

FWIW, I'd expect it to be a slight win overall; we'll see if profiling shows
otherwise, but...