If you are using Varnish version >= 2.1 and experiencing an ever increasing CPU usage up to a point where you need to restart the service to force CPU usage to drop you may want to add the “-h classic” argument to the command line.
This will revert to use the older hashing method instead of the newer “critbit” that was first introduced in version 2.1.
You can read a little bit more about it on the Yedda Dev Blog.
" doc_version: "1" last_updated: "2017-06-02" date: 2010-05-26 tags: [Caching, CPU, high cpu, http, Varnish, workaround] canonical: "https://eran.sandler.co.il/2010/05/26/varnish-high-ever-increasing-cpu-usage-workaround/" --- ## Sitemap - [Home](https://eran.sandler.co.il/) If you are using [Varnish][1] version >= 2.1 and experiencing an ever increasing CPU usage up to a point where you need to restart the service to force CPU usage to drop you may want to add the “-h classic” argument to the command line. This will revert to use the older hashing method instead of the newer “critbit” that was first introduced in version 2.1. You can read a little bit more about it on the [Yedda Dev Blog][2]. [1]: http://varnish-cache.org [2]: http://devblog.yedda.com/index.php/2010/05/26/varnish-2-1-ever-increasing-high-cpu-over-time-workaround/