Hi,
Regarding shared pool workers see CASSANDRA-11966. You may have to backport it
depending on your Cassandra version.
Did you try to lower compaction throughput to see if it helps? Be sure to keep
an eye on pending compactions, SSTables count and SSTable per read of course.
"alloc" is the memory allocation rate. You can see that compactions are GC
intensive.
You won't be able to achieve impressive writes/s with LWT. But maybe there is
room for improvement. Try GC tuning, different pool sizes for NTR, concurrent
reads and writes, compaction executors, etc. Also check if you can improve
network latency (e.g. VF or ENA on AWS).
What LWT rate would you want to achieve?
Best,
Romain
Le Lundi 27 février 2017 12h48, Kant Kodali <[email protected]> a écrit :
Also Attached is a flamed graph generated from a thread dump.
On Mon, Feb 27, 2017 at 2:32 AM, Kant Kodali <[email protected]> wrote:
Hi,
Attached are the stats of my Cassandra node running on a 4-core CPU. I am using
sjk-plus tool for the first time so what are the things I should watched out
for in my attached screenshot? I can see the CPU is almost maxed out but should
I say that is because of compaction or shared-worker-pool threads (which btw, I
dont know what they are doing perhaps I need to take threadump)? Also what is
alloc for each thread?
I have a insert heavy workload (almost like an ingest running against cassandra
cluster) and in my case all writes are LWT.
The current throughput is 1500 writes/sec where each write is about 1KB. How
can I tune something for a higher throughput? Any pointers or suggestions would
help.
Thanks much,kant
