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Date: Fri, 20 Dec 2024 22:35:34 +0100
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Subject: Re: [PHP-DEV] Discussion: Remove file statcache?
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To: Larry Garfield <larry@garfieldtech.com>,
 php internals <internals@lists.php.net>
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 =
From: cmbecker69@gmx.de ("Christoph M. Becker")

On 20.12.2024 at 20:26, Larry Garfield wrote:

> Background: PHP has a not-often-considered feature, the stat-cache.  Tha=
t is, the runtime caches the OS stat() call for files, so that subsequent =
reads on the same file can be faster.  However, it's even less realized th=
at it's a single-file cache.  It literally only applies when you try to do=
 two file-infomation operations on the same file in rapid succession, with=
out any other file reads in between.
>
> There's been some discussion about making the cache disable-able, though=
 the consensus now seems to be leaning toward getting rid of it outright:
>
> https://github.com/php/php-src/pull/17178
>
> Arnaud ran some quick benchmarks and found that disabling it has a less =
than 1% impact on Symfony and WordPress.
>
> https://github.com/php/php-src/pull/17178#issuecomment-2554323572
>
> Before we go any further, is there appetite among the voting population =
to remove it?  clearstatcache() and similar functions would get stubbed ou=
t as no-ops, but otherwise we'd just hand the responsibility back to the O=
S where it belongs, which seems so far like it would be almost an unmeasur=
able performance difference but remove some surprise complexity.
>
> Would you support such a removal?

I still think the stat cache should be *deprecated* first.  That gives
users a chance to reconsider calling multiple stat related functions
instead of doing a single stat() call.  See my previous comment[1] for
some further details.

[1] <https://github.com/php/php-src/pull/5894#issuecomment-2546473892>

Christoph