Hello, I set up cluster with 3 nodes/ 4Gram,4cores,raid0. I did experiment with stress.py to see how fast my inserts are. The results are confusing.
In each case stress.py was inserting 170KB of data: 1) stress.py was inserting directly to one node -dNode1, RF=3, CL.ONE 300000 inserts in 1296 sec (300000,246,246,0.01123401983,1296) 2) stress.py was inserting directly to one node -dNode1, RF=3, CL.QUORUM 300000 inserts in 987 sec (300000,128,128,0.00894131883979,978) 3) stress.py was inserting random into all 3 nodes -dNode1,Node2,Node3 RF=3, CL.QUORUM 300000 inserts in 784 sec (300000,157,157,0.00900169542641,784) 4) stress.py was inserting directly to one node -dNode1, RF=3, CL.ALL similar to case 1) ------- Im not surprising about cases 2,3) but the biggest surprise for me is why cl.one is slower then cl.quorum. CL.one has less "acks", shorter time of waiting... and so on. I was looking at some blogs about "write" architecture but the reason is still not clear for me. http://www.mikeperham.com/2010/03/13/cassandra-internals-writing/ http://prettyprint.me/2010/05/02/understanding-cassandra-code-base/ Thanks for advice. Best, Peter
