On 6/3/2013 3:33 PM, Greg Harris wrote:
You have to be careful looking at the QTime's. They do not include garbage collection. I've run into issues where QTime is short (cause it was), it just happened that the query came in during a long garbage collection where everything was paused. So you can get into situations where once the 15 second GC is done everything performs as expected! I'd make sure and have an external querying tool and you can monitor GC times as well via JMX.
The QTime value in the response is calculated using System.currentTimeMillis(), so it should include the GC time, unless the GC happens to hit just after the QTime is calculated but before the final response with all the results is sent. If you are requesting a lot of documents or you have very large documents where most/all of the fields are stored, having long GCs hit during that particular moment might actually be a common occurrence.
Thanks, Shawn
