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Date: Fri, 20 Mar 2015 11:40:50 +1100
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To: Eric Stenson <ericsten@microsoft.com>
Cc: "internals@lists.php.net" <internals@lists.php.net>
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Subject: Re: [PHP-DEV] [Q] Does PHP have a negative cache for file stat operations?
From: pierre.php@gmail.com (Pierre Joye)

On Fri, Mar 20, 2015 at 7:26 AM, Eric Stenson <ericsten@microsoft.com> wrote:
> PHP Internals folks--
>
> We're doing some performance work in WinCache, and we're finding that some frameworks are...uh...enthusiastically using file_exists(), is_file() and is_dir() functions on files/directories that don't exist.  Every. Single. Pageload.
>
> Does the PHP stat cache include negative cache entries?  If not, why not?
>
> Are there any existing extensions that implement a negative cache for file_exists(), is_file(), et. al.?

I suppose you mean to cache what does not exist? I think it is somehow
done, indirectly or this info could be detected using the stat cache
and the resolved path cache. However it may make this part of the
cache implementation a bit more trickier but it should be possible.

Cheers,
-- 
Pierre

@pierrejoye | http://www.libgd.org