[xwiki-devs] Preliminary memory tests

Hi, I've played a bit with Yourkit and a default XE to see the memory requirements. Here are some preliminary results (more tests needed): * After home page loaded: 38MB non-heap, 6377 classes * After code macro execution: 38 --> 52MB non heap, 8629 classes <--- a lot * After groovy macro execution: 52 --> 56MB, 9920 classes * After treeview + opened top level nodes: 56MB --> 63MB, 10960 classes <-- a lot * After Import: 63MB --> 65MB, 13036 classes * After Export: no change * After navigating a bit everywhere at random: heap memory needed: 155MB (used: 132MB), non heap: 65MB, classes: 13078 * After adding attachment of 1.1MB: almost no change * After deletion of 1.1MB attachment: used memory from 98MB to 132MB !! But still within the 155MB allocated heap memory Conclusion so far: ============== * We need around < 80MB non heap memory and < 200MB heap memory for the default XE pages and if the user manipulates attachments less than 1MB. * The default permgen size is 64MB so we're just above it (65MB). That's why some users have reported permgen issues I believe. Jython is eating a lot of it (14MB) * After adding a 7.3MB attachment: heap memory max from 155 to 261 (=>110MB!) * After removing it, need 297MB heap (even more) Second conclusion: ============== * Apart from attachments the memory needs seem reasonable IMO (< 255MB). * I'd still need to make sure I test all features of the wiki to be sure What more should I test? What should we do to reduce our permgen needs? Should we reduce it? Thanks -Vincent