Koha How-To

How to prevent thrashing

Recently we had a library that was consistently thrashing (processes stacking up. i.e. opac-search, ysearch, opac-detail) at one point in the day, multiple days in a row. After a conference call with the library we discovered that most of their computers were run from a computer image where the browsers cache had not been cleared. So each time a new image was loaded the browser had the same problem. This was consistently causing thrashing.

So two lessons:

  1. Clearing the browser cache for upgrades and clearing the browser cache when thrashing has been reported is VERY IMPORTANT.
  2. If you have anything that controls your public computers with images or snapshots or anything like that. Make sure that the image that you create has its browser cache cleared before you freeze it.

Clearing the cache

Read more by Mario Guilin

Tags systems tutorial