From: H. Peter Anvin <hpa@zytor.com>
Date: Thu, 01 Feb 2007 16:56:00 GMT
Subject: Re: .git/info/refs
Message-ID: <45C21BA0.4080700@zytor.com>
In-Reply-To: <Pine.LNX.4.63.0702011749100.22628@wbgn013.biozentrum.uni-wuerzburg.de>

Johannes Schindelin wrote:
> 
> Sorry, I should have been clearer. Plan:
> 
> 1. echo "Generating" > /htdocs/git/index.html
> 2. edit crontab to do this every minute:
> 2.1 gitweb is called directly_, to generate /htdocs/git/index.html.new
> 2.2 /htdocs/git/index.html.new is _moved_ into /htdocs/git/index.html, 
>     overwriting the existing one.
> 
> Yes, there could be two instances of this task concurrently. No, it does 
> not matter.
> 

Yes, it does matter, because it drives the load up further.  If you 
start having this going on in overlapping instances, then you're soon on 
the downhill slope of a cascading failure.

>> We can pre-generate the page before the first hit, but that's not a 
>> replacement for update-time caching.
> 
> It was only meant as a quick fix for the horrible workload.

And we have already experimented with it.  It unfortunately doesn't help 
much, it only makes matters worse.

	-hpa