Re: [RFC PATCH] index-pack: improve performance on NFS

From: Geert Jansen <gerardu@amazon.com>
Date: Nov 8, 2018, 20:58 UTC
Message-ID: <20181108205819.GA93589@amazon.com>
In-Reply-To: <20181108120256.GA29432@sigill.intra.peff.net>

On Thu, Nov 08, 2018 at 07:02:57AM -0500, Jeff King wrote:

Show 7 quoted lines

> Yes, testing and review. :)
> 
> I won't send the series out just yet, as I suspect it could use another
> read-through on my part. But if you want to peek at it or try some
> timings, it's available at:
> 
>   https://github.com/peff/git jk/loose-cache

I gave this branch a go. There's a performance regression as I'm getting a clone speed of about 100 KiB/s while with the previous patch I got around 20 MiB/s. The culprint appears to be a very large number of stat() calls on ".git/objects/info/alternates". The call stack is:

 -> quick_has_loose()
 -> prepare_alt_odb()
 -> read_info_alternates()

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