Hi,
I'm currently testing Cassandra 2.0.9 (and since the last week 2.1) under some read heavy load... I have 2 cassandra nodes (RF : 2) running under CentOS 6 with 16GB of RAM and 8 Cores. I have around 93GB of data per node (one Disk of 300GB with SAS interface and a Rotational Speed of 10500) I have 300 active client threads and they request the C* nodes with a Consitency level set to ONE (I'm using the CQL datastax driver). During my tests I saw a lot of CPU consumption (70% user / 6%sys / 4% iowait / 20%idle). C* nodes respond to around 5000 op/s (sometime up to 6000op/s) I try to profile a node and at the first look, 60% of the CPU is passed in the "sun.nio.ch" package. (SelectorImpl.select or Channel.read) I know that Benchmark results are highly dependent of the Dataset and use cases, but according to my point of view this CPU consumption is normal according to the load. Someone can confirm that point ? According to my Hardware configuration, can I expect to have more than 6000 read op/s ? Regards, Eric ________________________________ Ce message et les pi?ces jointes sont confidentiels et r?serv?s ? l'usage exclusif de ses destinataires. Il peut ?galement ?tre prot?g? par le secret professionnel. Si vous recevez ce message par erreur, merci d'en avertir imm?diatement l'exp?diteur et de le d?truire. L'int?grit? du message ne pouvant ?tre assur?e sur Internet, la responsabilit? de Worldline ne pourra ?tre recherch?e quant au contenu de ce message. Bien que les meilleurs efforts soient faits pour maintenir cette transmission exempte de tout virus, l'exp?diteur ne donne aucune garantie ? cet ?gard et sa responsabilit? ne saurait ?tre recherch?e pour tout dommage r?sultant d'un virus transmis. This e-mail and the documents attached are confidential and intended solely for the addressee; it may also be privileged. If you receive this e-mail in error, please notify the sender immediately and destroy it. As its integrity cannot be secured on the Internet, the Worldline liability cannot be triggered for the message content. Although the sender endeavours to maintain a computer virus-free network, the sender does not warrant that this transmission is virus-free and will not be liable for any damages resulting from any virus transmitted.
