Hi, i'm having a 5 node cluster with cassandra 3.0.13.
i could see the cassandra process has too many threads. *# pstree -p `pgrep java` | wc -l* *453* And almost all of those threads are in *sleeping* state and wait at *# cat /proc/166022/task/1698913/wchan* *futex_wait_queue_me* Some more info: *# strace -e trace=all -p 166022* *strace: Process 166022 attached* *futex(0x7efc24aeb9d0, FUTEX_WAIT, 166023, NULL* # cat /proc/166022/stack [<ffffffff810f5126>] futex_wait_queue_me+0xc6/0x130 [<ffffffff810f5deb>] futex_wait+0x17b/0x280 [<ffffffff810f7b26>] do_futex+0x106/0x5a0 [<ffffffff810f8040>] SyS_futex+0x80/0x180 [<ffffffff816b4fc9>] system_call_fastpath+0x16/0x1b [<ffffffffffffffff>] 0xffffffffffffffff What is the reason cassandra is having these many threads? is it the normal behavior of cassandra? Is there a way to reduce this thread count? will there be any performance impact because of this (our platform experts suspects so)? Regards, Renoy Paulose
