Is the "Threads" in your data the number of clients? How much heap space does each node have?
YCSB has a paper on their benchmark tests. You can try comparing your result with theirs and see if you have similarity. Best regards, Manoj On Tuesday, July 17, 2012, Code Box wrote: > I am doing Cassandra Benchmarking using YCSB for evaluating the best > performance for my application which will be both read and write intensive. > I have set up a three cluster environment on EC2 and i am using YCSB in the > same availability region as a client. I have tried various combinations of > tuning cassandra parameters like FSync ( Setting to batch and periodic ), > Increasing the number of rpc_threads, increasing number of concurrent reads > and concurrent writes, write consistency one and Quorum i am not getting > very great results and also i do not see a linear graph in terms of > scalability that is if i increase the number of clients i do not see an > increase in the throughput. > > Here are some sample numbers that i got :- > > *Test 1:- Write Consistency set to Quorum Write Proportion = 100%. FSync > = Batch and Window = 0ms* > > ThreadsThroughput ( write per sec ) Avg Latency (ms)TP95(ms) TP99(ms) > Min(ms)Max(ms) > > > 102149 3.1984 51.499291 1004070 23.82870 2.2260 2004151 45.96571301.7 > 1242 300419764.68 1154222.09 216 > > > If you look at the numbers the number of threads do not increase the > throughput. Also the latency values are not that great. I am using fsync > set to batch and with 0 ms window. > > *Test 2:- ** Write Consistency set to Quorum Write Proportion = 100%. > FSync = Periodic and Window = 1000 ms* > * > * > 1803 1.23712 1.012312.9Q 10015944 5.343925 1.21579.1Q 200196309.047 1970 > 1.17 1851Q > Are these numbers expected numbers or does Cassandra perform better ? Am i > missing something ? >
