Hi Emmanuel, I did some tests using the PingDelayInM, but without noticeable improvements.
With respect to the Nagle algorith, using Linux, I noticed no visible performance differences (CPU ~ 0%). Instead, I could get a 0% CPU load (yes, I've written it correctly!) with a RHEL 4 host running natively, and it sounds little strange for me (and maybe normal for you ^__^ ). The same operating system, running on a VirtualBox virtual machine, gives a 0% load, but the VM's instance uses 100% of CPU. May this is a "bug" of RHEL top util? Or some RedHat specific kernel patch? Or some incompatibility/regression/issue with new JVM and new kernels? Danilo Il Tuesday 29 April 2008 17:44:30 Emmanuel Cecchet ha scritto: > Hi Danilo, > > The driver is supposed to ping only every second according to the > default settings but you can try to override the value by appending the > following option to your JDBC URL: ?pingDelayInMs=60000 to force the > ping to happen only every minute. > Unfortunately, it looks like there is no way to turn this pinger thread > off. Also it looks like this fires daemon threads which can cause > problems if the JVM never stops (it will keep forking daemon thread each > time a new URL is accessed). > Another thing worth mentioning is that Sequoia disables the Nagle > algorithm on TCP connections (socket.setTcpNoDelay(true)). It would be > worth trying that on your client/server program to see if that changes > the performance. This might have a greater impact on Windows than Linux. > > > As you suggested, I played a little with networking options. First of all > > I did some more tests disabling group communication (no <Distribution> > > element in virtualdatabase config file, am I right?) , without any > > changes in results: [EMAIL PROTECTED] and receive0 with predominant cost. > > Yes, this is right. > > > May you suggest me other tests? > > Keep me posted with the results you obtain with the 2 options above. > > Thanks for your feedback, > Emmanuel _______________________________________________ Sequoia mailing list [email protected] https://forge.continuent.org/mailman/listinfo/sequoia
