Fwd: Re: Re: High CPU usage on some of the nodes due to message coalesce

Any cron or other scheduler running on those nodes? no Lots of Java processes running simultaneously? no, just Apache Cassandra Heavy repair continuously running? none Lots of pending compactions? none, the cpu goes to 100% on first seconds of insert (write load) so no memtable flushed yet,  Is

Re: Re: High CPU usage on some of the nodes due to message coalesce

I guess the code experts could shed more light on org.apache.cassandra.util.coalesceInternal and SepWorker.run. I'll just add anything I can think of Any cron or other scheduler running on those nodes? Lots of Java processes running simultaneously? Heavy repair continuously running? Lots of pe

Re: Re: High CPU usage on some of the nodes due to message coalesce

What takes the most CPU? System or User?  most of it is used by  org.apache.cassandra.util.coalesceInternal and SepWorker.run Did you try removing a problematic node and installing a brand new one (instead of re-adding)? I did not install a new node, but did remove the problematic node and CPU l

Re: Re: High CPU usage on some of the nodes due to message coalesce

se nodes are > decommissioned) > > Sent using Zoho Mail <https://www.zoho.com/mail/> > > > Forwarded message > From : Chris Lohfink > To : > Date : Sat, 20 Oct 2018 23:24:03 +0330 > Subject : Re: High CPU usage on some of the nodes due to

Fwd: Re: High CPU usage on some of the nodes due to message coalesce

Chris Lohfink To : Date : Sat, 20 Oct 2018 23:24:03 +0330 Subject : Re: High CPU usage on some of the nodes due to message coalesce Forwarded message 1s young gcs are horrible and likely cause of some of your bad metrics. How large are your mutations/query results and

Re: High CPU usage on some of the nodes due to message coalesce

1s young gcs are horrible and likely cause of some of your bad metrics. How large are your mutations/query results and what gc/heap settings are you using? You can use https://github.com/aragozin/jvm-tools to see the threads generating allocation pressure

High CPU usage on some of the nodes due to message coalesce

3 nodes in my cluster have 100% cpu usage and most of it is used by  org.apache.cassandra.util.coalesceInternal and SepWorker.run? The most active threads are the messaging-service-incomming. Other nodes are normal, having 30 nodes, using Rack Aware strategy. with 10 rack each having 3 nodes. The