Planet Varnish

  • Thread organization in Varnish Cache 4.0 One of the two biggest changes in Varnish 4.0 is how the threads work. Varnish uses threads for doing all the heavy lifting and it seems to be working out quite well. In Varnish 3.0 one thread would service each client, doing whatever that client wanted it to do. Within reason, obviously. These are very decent threads. The thread would deliver from cache, fetch content from the backend, pipe, etc. 2014-04-16T07:44:58Z
  • Frontend/Senior Software Developer wanted in our London or Oslo office Exciting open source company seeks Frontend/Senior Software Developer in our London or Oslo office. 2014-04-14T13:01:44Z
  • Varnish 4.0.0 released This is a major feature release with a lot of big changes from the last version released 2.5 years ago. Some prominent examples include: Full support for streaming objects through from the backend on a cache miss. Bytes will be sent to 1..n requesting clients as they come in from the backend server. Background (re)fetch […]
  • Logging in Varnish 4.0 The logging in Varnish Cache is one of the unique features of Varnish that in my mind sets it apart from the rest of the software world. It combines both logging in great detail with both performance, manageability, sensible privacy defaults and access to great debugging help. The shared memory log, logs everything that happens without the need to adjust log levels or without significantly affecting performance, eliminating the need for turning on any debug switch. Many of you have surely been in a situation where you have an application that is misbehaving. Then you increase the log level to debug and the problem magically disappears - obviously caused by the application slowing down just enough that the race condition you encountered earlier is now gone. The weakness of logging everything is that so much information is available that the administrator can sometimes be overwhelmed by all the information presented. It’s a figurative firehose of information and drinking from it can be painfull.  Martin has reimplemented a new logging framework in Varnish Cache 4.0. Out of all the new stuff in Varnish Cache 4.0 this might be the most significant one. It’s also the most complex feature, requiring quite a bit of time to fully understand how it works. 2014-04-09T16:12:38Z
  • Converting a Varnish 3.0 VMOD to 4.0 So we’re getting closer to releasing the first proper 4.0 version of Varnish Cache. One of the things we need to fix is to get all the vmod writers to make sure their vmod works with the new version. Here … Continue reading →