cocoon-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From gor...@3months.com
Subject Re: Tomcat Versions and Garbage Collection
Date Tue, 09 Mar 2004 09:31:50 GMT
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: jh@domek.be
To: users@cocoon.apache.org
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: users-unsubscribe@cocoon.apache.org
>For additional commands, e-mail: users-help@cocoon.apache.org
>



---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@cocoon.apache.org
For additional commands, e-mail: users-help@cocoon.apache.org


Mime
View raw message