Hi all,
I have a cluster of three nodes and would like to ask some questions about the
performance.
I wrote a small benchmarking tool in java that mirrors (read, write) operations
that we do in the real project.
Problem is that it is not scaling like it should. The program runs two tests:
one using batch statement and one without using the batch.
The operation sequence is: optional select, insert, update, insert. I run the
tool on my server with 128 threads (# of threads has no influence on the
performance),
creating usually 100K resources for testing purposes.
The average results (operations per second) with the use of batch statement are:
Replication Factor = 1 with reading without reading
1-node cluster 37K 46K
2-node cluster 37K 47K
3-node cluster 39K 70K
Replication Factor = 2 with reading without reading
2-node cluster 21K 40K
3-node cluster 30K 48K
The average results (operations per second) without the use of batch statement
are:
Replication Factor = 1 with reading without reading
1-node cluster 31K 20K
2-node cluster 38K 39K
3-node cluster 45K 87K
Replication Factor = 2 with reading without reading
2-node cluster 19K 22K
3-node cluster 26K 36K
The Cassandra VMs specs are: 16 CPUs, 16GB and two 32GB of RAM, at least 30GB
of disk space for each node. Non SSD, each VM is on separate physical server.
The code is available here https://github.com/bjanosik/CassandraBenchTool.git .
It can be built with Maven and then you can use jar in target directory with
java -jar target/cassandra-test-1.0-SNAPSHOT-jar-with-dependencies.jar .
Thank you for any help.
