I messed with a perfectly good 1.3 setup and installed Solr 1.4 in the hope of seeing better faceting performance. Nothing in the release notes or migrating section scared me off. I stuck with it a little too long and now due to the costs of rebuilding the time delta on the index I am committed. I'm now having a lot of problems with uptime, the Solr instances just get in a place where they spend all their time doing GC (even before reaching Xmx sometimes). I've since turned off nearly all faceting (using enum currently, switching to fc did not change anything) and dropped the FilterCache size back into stratospheric levels. I realized, with the new FieldCache stuff, I no longer understand the performance levers involved. At first, I thought upping permgen space from 192->256MB helped. I soon found myself in the same boat as I was before.
I have two Solr 1.4 slaves, both a single quad core Xenon (from about 1.5 years ago) and 16GB of RAM. The index is closing in on 70GB (was >120GB long ago but cut down on a lot of the stored fields, useless data, etc). I do a very low volume of searches by count. My old working and stable 1.3 config was: -server -d64 -Xmx12g -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:+UseParNewGC Trying to get stability... I've [had the perception of] SLIGHT improvements by adding -XX:+CMSClassUnloadingEnabled -XX:+CMSIncrementalPacing -XX:CMSInitiatingOccupancyFraction=50 I've also toyed with removing some of these and even using the parallel collector (which worked great for me when I was at CNET... but on a much much smaller collection and a much older java). Nothing seems to help. # java -version java version "1.6.0_18" Java(TM) SE Runtime Environment (build 1.6.0_18-b07) Java HotSpot(TM) Server VM (build 16.0-b13, mixed mode) How do I control how much heap the FieldCache will use? Are there any good resources out there that will help me understand the performance impacts and tuning for FieldCache? Is there anything new in 1.4 besides the FC that I should be looking at? I obviously don't have enough info here to place blame on the FC. I added a FieldValueCache as per the new sample solrconfig.xml ... but I've never seen anything appear in there ... I presume I will only see entries when I am using the fc faceting method. Any suggestions on a change to my GC settings or solrconfig.xml to match with changes in 1.4? I'm going to add an SSD L2ARC to get some better performance but that will not help my GC issues. Trey Hyde th...@centraldesktop.com Central Desktop, Inc. Organize, Share, Collaborate
