Thanks. I'll pursue that angle - and see if there is a way, in Tapestry to just not create the session.
(If anyone has any suggestions on where I can look for an answer to that - I'm all ears...) -- Robin D. Wilson Director of Web Development KingsIsle Entertainment, Inc. CELL: 512-426-3929 DESK: 512-623-5913 www.KingsIsle.com -----Original Message----- From: Rainer Jung [mailto:rainer.j...@kippdata.de] Sent: Saturday, January 09, 2010 6:11 AM To: Tomcat Users List Subject: Re: When running under high load (via load generating tools), Tomcat 6.0.20 stops expiring sessions until the load subsides; causing thrashing on Garbage Collection On 09.01.2010 12:13, Mark Thomas wrote: > On 08/01/2010 23:07, Robin Wilson wrote: >> OK, I made the following changes (1 at a time) to 'server.xml', and retested: >> >> <Manager className="org.apache.catalina.ha.session.DeltaManager" >> expireSessionsOnShutdown="false" >> processExpiresFrequency="1" >> notifyListenersOnReplication="true"/> >> >> No discernable difference was noted on the retest (NOTE: I have measured the >> sessions vs. the number of 'threads requesting pages', and I think that the >> sessions are actually expiring - just _much_ slower than my load generator >> is creating them. So I'm creating 100,000 sessions in 'n' time period, and >> in that same time period only 6,000 are being expired and removed (the ratio >> seems pretty constant - ~94% of the sessions created are staying around). >> >> Then I made this change to 'server.xml': >> >> <Engine >> name="tomcat" >> backgroundProcessorDelay="1" >> defaultHost="localhost"> >> >> Again, no discernable difference in behavior. >> >> So, new question - is there a way to tell Tomcat to clear out larger numbers >> of sessions at once? (Assuming they are past their "inactivity duration" >> period?) Even when I shut off the load generators, it only clears the >> sessions at a rate of a few thousand every second. > > Given it works when the load is reduced, it looks like the expiration > logic is correct. One thing that would give you a bit more information > is setting the log level for org.apache.catalina.session.ManagerBase to > debug. > > I wonder if you are simply creating sessions faster than the single > background thread can clear them out. If that is the case, how realistic > is your load? I'm happy to try a fix a genuine issue but I don't think > there is much benefit in making changes to address an artificial problem. Seconding Mark: it seems for those "1 second idle timeout" sessions you are not using the session at all. So why are you generating a huge number of sessions you are never going to use? Regards, Rainer --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
