hi Jorg I hadn't thought of Jetty, good point. I'll give it a go when I get the chance. I'd also be interested if anyone else can repeat these results.
Cheers Gordon Gordon Anderson 3months.com ---- Original Message ---- From: [EMAIL PROTECTED] To: [EMAIL PROTECTED] Subject: Re: Tomcat Versions and Garbage Collection Date: Tue, 09 Mar 2004 09:37:16 +0100 >Very useful info thanks! > >Are you in a position to run this bench on Jetty as well? > >Jorg > >Gordon Anderson wrote: > >> hi >> >> I've been looking into variations of performance with different >versions >> of Tomcat to serve a website of approximately 6000 URLs using >Cocoon >> 2.1.4. Performance was noticeably slower using Tomcat 4, the >reason >> being garbage collection. >> >> To turn garbage collection on using the Sun JVM, append >> >> -Xloggc:/opt/tomcat/logs/garbage.log >> >> to the CATALINA_OPTS variable, where /opt/tomcat is the location of >your >> Tomcat instance. >> >> Crawling the site using the free Xenu crawler tool, performance >under >> Tomcat 4.1.27 degraded significantly after around 1000 URLs. >Examining >> the logs, the reason was soon obvious. >> >> 1334.524: [Full GC 518449K->518079K(518464K), 2.5774490 secs] >> 1337.102: [Full GC 518079K->518079K(518464K), 2.5330770 secs] >> 1339.654: [Full GC 518458K->518188K(518464K), 2.5701920 secs] >> 1342.224: [Full GC 518188K->518179K(518464K), 2.5360680 secs] >> 1344.802: [Full GC 518456K->518233K(518464K), 2.5695450 secs] >> 1347.371: [Full GC 518233K->518214K(518464K), 3.2225810 secs] >> 1350.610: [Full GC 518403K->518180K(518464K), 2.5540920 secs] >> 1353.164: [Full GC 518180K->518178K(518464K), 2.5558220 secs] >> >> >> It was spending all its time garbage collecting! >> >> >> >> Using Tomcat 5.0.19, after approx 30000 hits on the site, the log >is >> certainly more pleasing: >> 13435.211: [GC 749150K->686258K(765332K), 0.1123580 secs] >> 13442.140: [GC 755121K->692181K(765332K), 0.1140720 secs] >> 13449.131: [GC 761045K->700089K(769044K), 0.1324210 secs] >> 13449.265: [Full GC 700089K->233002K(769044K), 1.8186920 secs] >> 13460.298: [GC 301859K->245577K(765332K), 0.1021830 secs] >> 13468.507: [GC 314440K->254022K(765332K), 0.1221460 secs] >> 13476.208: [GC 322886K->259107K(765332K), 0.1037680 secs] >> 13482.677: [GC 327971K->267097K(765332K), 0.1375070 secs] >> 13492.732: [GC 335961K->274713K(765332K), 0.1315550 secs] >> 13500.313: [GC 343577K->279775K(765332K), 0.1020140 secs] >> 13508.526: [GC 348634K->286971K(765332K), 0.1172210 secs] >> 13517.606: [GC 355831K->292747K(765332K), 0.1061540 secs] >> >> >> As you can see the Full GC (Full Garbage Collect) is happening >> sporadically, thus server performance is improved. >> >> >> It should be noted that exactly the same WAR file and tomcatd / >> CATALINA_OPTS were used for both versions of Tomcat. >> >> >> The parameters I have changed from the default installation: >> >> garbage collection logging as above >> set max heap size to 1000M >> made NO CHANGES to the store janitor parameters >> set all pool-max values for the objects I am using to 1024 >> >> Use Tomcat 5.0.19, JDK 1.4.2 >> CIncludes cached for 12 hours >> Apache serving static files >> >> >> As a little side note after the crawl had finished, I saw 700M of >heap >> space being reclaimed by a garbage collect :) This would indicate >that >> the memory issues that were inherent with 2.1.2 have disappeared. >> >> >> I hope the above is of interest to those having performance >problems >> >> >> Cheers >> >> Gordon >> >> Gordon Anderson >> 3months.com > > >--------------------------------------------------------------------- >To unsubscribe, e-mail: [EMAIL PROTECTED] >For additional commands, e-mail: [EMAIL PROTECTED] > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
