From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH] gitweb: Support caching projects list
Date: Thu, 13 Mar 2008 17:19:53 -0700
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To: Petr Baudis <pasky@suse.cz>
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Petr Baudis <pasky@suse.cz> writes:

> To prevent contention when multiple accesses coincide with cache
> expiration, the timeout is postponed to time()+120 when we start
> refreshing. When showing cached version, a disclaimer is shown at the
> top of the projects list.

Isn't this still racy when two requests come at about the same time?
Perhaps you can avoid it by using a lockfile?