On 10/28/2015 5:11 PM, Rallavagu wrote: > Seeing very high CPU during this time and very high warmup times. During > this time, there were plenty of these errors logged. So, trying to find > out possible causes for this to occur. Could it be disk I/O issues or > something else as it is related to commit (writing to disk).
Lucene is claiming that you're hitting the Out Of Memory exception. I pulled down the 4.6.1 source code to verify IndexWriter's behavior. The only time hitOOM can be set to true is when OutOfMemoryError is being thrown, so unless you're running Solr built from modified source code, Lucene's claim *is* what's happening. In OOM situations, there's a good chance that Java is going to be spending a lot of time doing garbage collection, which can cause CPU usage to go high and make warm times long. The behavior of most Java programs is completely unpredictable when Java actually runs out of memory. As already mentioned, the parts of Lucene that update the index are specifically programmed to deal with OOM without causing index corruption. Writing code that is predictable in OOM situations is challenging, so only a subset of the code in Lucene/Solr has been hardened in this way. Most of it is as unpredictable in OOM as any other Java program. Thanks, Shawn
