Hello,
I'm using: Solr 5.2.1 10 shards each with a replica. (20 nodes in total) Zookeeper 3.4.6. About half a year ago we upgraded to Solr 5.2.1 and since then have been experiencing a 'wipe out' effect where all of a sudden most if not all nodes will go down. Sometimes they will recover by themselves but more often than not we have to step in to restart nodes. Nothing in the logs jumps out as being the problem. With the latest wipe out we noticed that 10 out of the 20 nodes had garbage collections over 1min all at the same time, with the heap usage spiking up in some cases to 80%. We also noticed the amount of selects run on the solr cluster increased just before the wipe out. Increasing the heap size seems to help for a while but then it starts happening again- so its more like a delay than a fix. Our GC settings are set to -XX: +UseG1GC, -XX:+ParallelRefProcEnabled. With our previous version of solr (4.10.0) this didn't happen. We had nodes/shards go down but it was contained, with the new version they all seem to go at around the same time. We can't really continue just increasing the heap size and would like to solve this issue rather than delay it. Has anyone experienced something simular? Is there a difference between the two versions around the recovery process? Does anyone have any suggestions on a fix. Many thanks Philippa
