Hi, I am trying a RAIDb-1 Sequoia cluster. My configuration consists of: - one or two dedicated controllers - each controller supported by 2 PostgreSQL or MySQL hosts as backends Each controller was tested with different operating systems: - Slackware 12.0 (with kernel 2.6.21.5-smp SMP) - Debian 4 (2.6.18-4-686 SMP) - Gentoo (2.6.24) - RedHat Enterprise 4 (2.6.9-5.ELsmp SMP) - Windows XP Professional SP 2 with different Java VMs: - J2RE 1.4.2 - JDK 1.5.0_15 - JDK 1.6 and with different hardware: - 2 [EMAIL PROTECTED], 2Gb Ram - Pentium 4 [EMAIL PROTECTED], 2 Gb Ram - Pentium 4 @3GHz, 512 Mb Ram - Virtual Machine
With all the configurations, using the tool JDBCBench (executed from a dedicated host), I noticed a big cpu load on the controller and very poor performance. For example, with a direct access to a single PostgreSQL node I can reach 3500 transactions/sec, instead of a 800txn/s obtained by a controller with 2 PostgreSQL hosts. In the latter case, the DB hosts are not overloaded: PostgreSQL (and MySql) uses about 5% CPU and generate only 150Kbyte/s network traffic. I tried to use both JGroups and Appia (both SEQ and TOKEN, UDP and TCP) with the same results (only few differences, but always with high cpu load). I also tried Sequoia 2.10.9, 3.0-beta2 and 3.0-beta3 (I can't use cvs version because I get a null pointer exception in Controller.java:185, in function sendJmxNotification(), with respect to notificationBroadcasterSupport). I used the last available JDBC drivers for PostgreSQL (postgresql-8.2-508.jdbc3.jar) and for MySQL (mysql-connector-java-5.1.5-bin.jar). I also enabled cache and disabled SQL monitoring, without big improvements. Also tried different schedulers (RoundRobin and LeastPendingRequestsFirst), with both WaitForCompletion policy "all" and "first". >From the published presentations, I can read that the performance with Sequoia should increase, whereas in my case they decrease (I need about 3 controllers, each one with 2 backends, to reach the same performance of a single PostgreSQL host). Searching in the mailing list I read some users with the same problems, but I could not find a solution. Any help is very appreciated. Yours faithfully, Danilo Levantesi _______________________________________________ Sequoia mailing list [email protected] https://forge.continuent.org/mailman/listinfo/sequoia
