Jenkins GUI very slow - fast after browser cache clear

Question

We have a Jenkins master + 5 slaves setup.

The recent weeks the Jenkins GUI has started slowing down for us, up to the point that loading of Jenkins GUI periodically takes minutes. After loading it is still slow, Jenkins does not feel very responsive at all.

Curiously, when I open Jenkins AND clear all browser caches (cookies, cache etc) the Jenkins GUI is blazing fast, everything loads fine then. The next day the GUI also starts to slow down, until I clear all browser cookies + caches again. I tested this in Chrome + IE, same results.

Some things I already checked and tried:

• Check CPU + memory usage on the master (low CPU usage, plenty heap space free)
• GC logs on master (checked on gceasy - everything is alright - no suggestions)
• Cleared old data on Jenkins
• We already restricted all jobs to have a max history of 10

So, I'm out of ideas. It is something related to the browser/client since clearing the cookies/cache fixes the problem for users.

Any ideas what may be the real problem with Jenkins?

When the GUI is loaded and slow, what I see that many requests to static resources are very long pending, eg. this resource: /static/1f01833b/images/32x32/red_anime.gif

Answer 1

Update: This is the Jira ticket regarding this issue:

https://issues.jenkins-ci.org/browse/JENKINS-56243

Quite a few people are having the same problem, and Active Directory does not seem the root cause because people report having the same issue without AD integration. Unfortunately the Jenkins developers do not seem to give it much priority...