Re: kernel.org mirroring (Re: [GIT PULL] MMC update)

From: H. Peter Anvin <hpa@zytor.com>
Date: Dec 7, 2006, 19:16 UTC
Message-ID: <457868AA.2030605@zytor.com>
In-Reply-To: <Pine.LNX.4.64.0612071052560.3615@woody.osdl.org>

Linus Torvalds wrote:

Show 9 quoted lines

> 
> On Thu, 7 Dec 2006, H. Peter Anvin wrote:
>> That all being said, the lack of intrinsic caching in gitweb continues to be a
>> major problem for us.  Under high load, it makes all the problems worse.
> 
> I really don't see what gitweb could do that would be somehow better than 
> apache doing the caching in front of it.. Is there some apache reason why 
> that isn't sufficient (ie limitations on its cache size or timeouts?)
>

What it could do better is it could prevent multiple identical queries from being launched in parallel. That's the real problem we see; under high load, Apache times out so the git query never gets into the cache; but in the meantime, the common queries might easily have been launched 20 times in parallel. Unfortunately, the most common queries are also extremely expensive.