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Subject: "VM Thread" taking 100% CPU?
From: Yang <teddyyyy123@gmail.com>
To: user@cassandra.apache.org
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I'm running my cassandra cluster (one node), it went fine for a while
under heavy load , using 270% CPU etc (this is a multi-core machine).
but after a while, the CPU utilization dropped to 100%, and the
cluster stopped responding to requests.

I did a jstack , and did

ps ax -L -o tid,pid,%cpu,command|less


I found that one thread is taking 45% of CPU, and the corresponding
entry in the jstack output is:


"VM Thread" prio=10 tid=0x09a50400 nid=0x1a1a runnable


what is the "VM Thread" ?
youkit dump does not show a thread with this name

Thanks
Yang