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
And almost all of those threads are in sleeping state and wait at
# cat /proc/166022/task/1698913/wchan
Some more info:
# strace -e trace=all -p 166022
strace: Process 166022 attached
futex(0x7efc24aeb9d0, FUTEX_WAIT, 166023, NULL
# cat /proc/166022/stack
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)?