Hi,
I'm trying to evaluate performance of Apache Cassandra V4.0.1 for write-only workloads using on-premise physical servers. On a single node cluster, doing some optimizations i was able to make CPU of node >90%, throughput is high enough and CPU is the bottleneck as i expected. Then doing the same benchmark on a cluster with two nodes/RF=2/CL=ALL, the throughput decreased by 20% in compare with single node scenario but CPU usage on both nodes is about 70%(changing from 50% to 90% over and over again each 5-6 seconds), i wonder how could i make CPU usage >90% steadily in this scenario so reach maximum throughput of my Hardware (resources other than CPU being used by less than 10% of their capability) >From jvisualvm: There are only 90 Native-Transport threads mostly waiting and >31 Mutation stage threads also mostly waiting, the only threads that are >always running are Messaging-EventLoop (6 threads) and epollEventLoop (40 >threads). Where is the bottleneck of the cluster now? How can i increase its resources to again reach 90% CPU and max write throughput? How can i debug pipeline of SEDA architecture of Cassandra to find such bottlenecks? Best Regards Sent using https://www.zoho.com/mail/
