August 14, 2010
At $WORK I’m currently working on deploying a pool of Varnish servers to sit in front of some Apache servers running Pressflow. On our current infrastructure we’ve been running Squid for the past few years with very good success , minus a hiccup or two along the way, one involving memory fragmentation (thank you tcmalloc). Varnish has a few nice features that Squid lacks.
The ability to PURGE objects using wildcards Better support for multiple processors (Squid can benefit from multi procs when using AUFS) Grace period that can be configured to serve objects from the cache after they’ve expired while fetching the new content from the backend.