I'm new to solr and I'm load testing our setup to see what we can handle. I'm using solrmeter and my problem is a bit odd:
- When I set solrmeter to run 8000 queries/min, it will handle a few hundred queries and then tomcat will stop responding completely to requests (even though according to
lsof -iit is still listening and the java process is still running).
- When I set solrmeter to run 1000 queries/min it runs fine. I can stop solrmeter after a few minutes and then run 8000/min without issue.
It's as if it needs a ramp up time? Also, I noticed (regardless of ramp up) that my setup cannot handle 12000/min. The reaction at 12k/min is the same as if I were to run 8k/min without the ramp up. Of note, only the shard that solrmeter is pointed to stops responding. The other shard hums along without incident.
Setup (everything in AWS):
- 2x m1.large (7.5Gb RAM) running tomcat7 + solr 4.2.0 (open-jdk-7-headless) : Ubuntu 12.04
- 1x m1.micro running zookeeper 3.4.5 : Ubuntu 12.04
The vast majority of my solr/tomcat7 config is default from ubuntu's packages/solr's example. Here's the configs and the end of the catalina.out file: https://gist.github.com/anonymous/ef8fa79ecc1673d11bc0
I redirected the solrmeter console (stderr and stdout) to a file. Its a large log (67Mb): https://docs.google.com/file/d/0BwPYmFCfmBYsU1hDWjlkUGdGTlU/edit?usp=sharing
My main question is two fold:
- Is this normal behavior for tomcat (to just stop responding completely) when it gets overwhelmed? And the only option is to restart it?
- Why does it handle better when I give it a lower number of queries and then ramp it up? It concerns me that if I have to restart a server in the cluster and it gets thrown into the pool of machines that things will blow up.