Re: [PATCH] inotify to minimize stat() calls

From: Duy Nguyen <pclouds@gmail.com>
Date: Apr 25, 2013, 21:20 UTC
Message-ID: <CACsJy8ChXRMR93r2R5NoTL7Ly1HqWCXq=t=Kj4ma5+MyYvESpg@mail.gmail.com>
In-Reply-To: <CAKXa9=pt2mxwFtepoOLZ-Atw3Ey5_OHh6rzk43kVTs8=vcVuRw@mail.gmail.com>

On Fri, Apr 26, 2013 at 2:44 AM, Robert Zeh <robert.allan.zeh@gmail.com> wrote:

Show 9 quoted lines

>> Can you just replace lstat/stat with cached_lstat/stat inside
>> git-compat-util.h and not touch all files at once? I think you may
>> need to deal with paths outside working directory. But because you're
>> using lookup table, that should be no problem.
>
> That's a good idea; but there are a few places where you want to call
> the uncached stat because calling the cache leads to recursion or
> you bump into things that haven't been setup yet.  Any ideas how to
> handle that?

On second thought, no my idea was stupid. We only need to optimize lstat for certain cases and naming cached_lstat is much clearer. I suspect read-cache.c and maybe dir.c and unpack-trees.c are the only places that need cached_lstat. Other places should not issue many lstats and we don't need to touch them. -- Duy