I suggest upgrading to either 0.6.12 or 0.7.4 and re-testing. On Mon, Mar 21, 2011 at 12:52 PM, Markus Klems <markuskl...@gmail.com> wrote: > Hi guys, > > we are currently benchmarking various configurations of an EC2-based > Cassandra cluster. This is our current setup: > > 1) 8 nodes where each node is an m1.xlarge EC2 instance > 2) Cassandra version 0.6.5 > 3) Replication Factor = 3 > 4) this delivers ~7K to 10K ops/sec with 50% GET and 50% INSERT > depending on the consistency level > > We have been benchmarking the cluster with YCSB, while altering the > consistency levels ONE, QUORUM, and ALL, ceteris paribus. This works > fine if all nodes are alive. Then, we wanted to benchmark the cluster > performance behavior when one node goes down. So, we killed one node > and tested the cluster with consistency level ONE, which delivered > reasonable throughput of multiple thousand ops/sec. Then, we wanted to > test QUORUM and ALL. However, when one node is down, the cluster > throughput sharply drops to a few operations and then stops responding > to the YCSB client if the consistency level of operations in the > benchmark is set to QUORUM or ALL. For ALL, this behavior would (kind > of) make sense for read requests but we are puzzled that even QUORUM > won't work. And for 100% write operations in consistency level ALL it > won't work either. > > Any ideas why the cluster stops responding for QUORUM and ALL? > > Thanks, > > Markus >
-- Jonathan Ellis Project Chair, Apache Cassandra co-founder of DataStax, the source for professional Cassandra support http://www.datastax.com
