ES uses several threadpools. Some are fixed sized, some are scalable, and the reference is the JVM available core count, i.e. Runtime.getRuntime().availableProcessors(), which can be overridden by a "processors" directive:
http://www.elastic.co/guide/en/elasticsearch/reference/current/modules-threadpool.html I have 32 cores per machine so I'm also observing hundreds of idle threads. I do not use percolators/warmers/snapshot/suggest in my use case. Since they are not active, they steal a lot of my stack memory. Right now I don't care about idle threads but this can be a problem for small memory sized machines. If you feel safe about reducing thread pool resources, you can decrease them in your config, e.g. -Des.processors=4. But you should monitor your performance, if you see bad numbers, go back to default. Jörg On Mon, Mar 23, 2015 at 8:48 AM, Abid Hussain <[email protected]> wrote: > Thanks Jörg, I did a thread dump: 60 % of ~400 threads are in state > WAITING, 35 % are in state RUNNABLE, the rest is in state TIMED_WAITING, > none is in state BLOCKED. > > So I assume everything is OK - still wondering whats the point of creating > hundreds of threads as there are "only" 24 cores available on our machine. > > Best regards, > > Abid > > Am Freitag, 20. März 2015 16:47:28 UTC+1 schrieb Jörg Prante: >> >> I think you should check a thread dump created by tools like jstack if >> you have a high JVM thread count in state BLOCKED. This might be a pointer >> that something unusual is going on, but I'm not sure. >> >> Jörg >> >> >>> -- > You received this message because you are subscribed to the Google Groups > "elasticsearch" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/elasticsearch/e0cef7f2-9f38-4c16-806d-45fbd3dc14a1%40googlegroups.com > <https://groups.google.com/d/msgid/elasticsearch/e0cef7f2-9f38-4c16-806d-45fbd3dc14a1%40googlegroups.com?utm_medium=email&utm_source=footer> > . > > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "elasticsearch" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/elasticsearch/CAKdsXoF%2B2jrzPH6w%2BHa9v6ixJXOYS8Rdu_%3DMdRc5PVDG6%3DK8-g%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
