Re: Webapp slow down after idle - 5.5.x
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 All, On 2/22/2010 2:14 PM, Peter Crowther wrote: On 22 February 2010 19:07, Caldarale, Charles R chuck.caldar...@unisys.com wrote: Sounds like the OS might be paging out Tomcat, and taking a long time to get all the necessary pages back in when a request is made. I'm not familiar with operational details of AIX, but I would suspect there are some system-level monitoring tools available to see if there is a paging spike in this situation. vmstat (http://publib.boulder.ibm.com/infocenter/aix/v6r1/index.jsp?topic=/com.ibm.aix.cmds/doc/aixcmds6/vmstat.htm) would do the job. No finesse, but sufficient information :-). +1 If Tomcat/JVM is being swapped-out or otherwise passivated, a simple are you alive script can be scheduled to run at intervals to keep Tomcat in memory. Something like every hour or maybe every minute, you could make a request to some trivial page like /ping.jsp. Another possibility is that your webapp uses database connections which are becoming stale during these periods of inactivity. Oracle, specifically, is well-known for taking a long time to re-establish a database connection, so it's possible you're waiting for that to happen after these idle times. Several solutions are possible, including: 1. Use the ping.jsp technique to also issue a trivial query against the database 2. Change your database connection configuration to allow for longer idle times - -chris -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.10 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAkuEJwEACgkQ9CaO5/Lv0PDZCwCeM8Yc259GpiqPB/KkgotGdBVL epsAoID+/TlQ8FQSB4/4LpKLIsKewfhT =EuRI -END PGP SIGNATURE- - To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
Re: Webapp slow down after idle - 5.5.x
On Tue, Feb 23, 2010 at 11:05 AM, Christopher Schultz ch...@christopherschultz.net wrote: Something like every hour or maybe every minute, you could make a request to some trivial page like /ping.jsp. Which is exactly what a service monitor like Nagios does -- plus it lets you know if the proper response isn't received (no response, error page/wrong page size, etc.). I would think every production system would have something like that in place as a matter of course. -- Hassan Schroeder hassan.schroe...@gmail.com twitter: @hassan - To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
Re: Webapp slow down after idle - 5.5.x
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hassan, On 2/23/2010 2:19 PM, Hassan Schroeder wrote: On Tue, Feb 23, 2010 at 11:05 AM, Christopher Schultz ch...@christopherschultz.net wrote: Something like every hour or maybe every minute, you could make a request to some trivial page like /ping.jsp. Which is exactly what a service monitor like Nagios does -- plus it lets you know if the proper response isn't received (no response, error page/wrong page size, etc.). I would think every production system would have something like that in place as a matter of course. I would think so. We have our own that reports heap usage, database connection pool usage, and the patch level of the JVM. We can use it to graph memory usage over long periods of time using whatever sampling rate we choose, because it's all based upon when the request is made. Every 5 minutes? No problem. Every 5 seconds? Just change the cron job. :) - -chris -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.10 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAkuETK8ACgkQ9CaO5/Lv0PCdVwCfWqWqmEloAvZvjDCuGs8LdTzh C0UAoKOxjXHGvi0QoOPQkhyvjl9uStn2 =Uxtn -END PGP SIGNATURE- - To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
Webapp slow down after idle - 5.5.x
Hello, My webservice (using axis 1.1)is deployed on tomcat 5.5.28. Tomcat runs on AIX and IBM Java 1.5 SR9. The problem is that every first request after a longer idle (like a day) is served very slow. There's no performance problem with next requests. It looks quite similar to first request after tomcat restart yet there's no restart here. It's very difficult to spot the problem since most of the time everything runs fine and I have like one chance a day to test some new options. Any ideas about that ? Thanks in advance, Kate -- Kup wlasne mieszkanie za 72 tys. zl. Sprawdz najlepsze oferty http://link.interia.pl/f25a8 - To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
Re: Webapp slow down after idle - 5.5.x
One thing that comes to mind is virtual memory swapping. If Tomcat is idle for a long time, all of its memory may be swapped out to disk to make room for other programs. Then when Tomcat needs to handle a request, it must be swapped back in from disk which takes time. I've observed the hard disk light flickering when this happens but I don't know if you want to spend the night camping in the server room watching for this. -- Len On 2010-02-22, at 13:29, klin...@poczta.fm wrote: Hello, My webservice (using axis 1.1)is deployed on tomcat 5.5.28. Tomcat runs on AIX and IBM Java 1.5 SR9. The problem is that every first request after a longer idle (like a day) is served very slow. There's no performance problem with next requests. It looks quite similar to first request after tomcat restart yet there's no restart here. It's very difficult to spot the problem since most of the time everything runs fine and I have like one chance a day to test some new options. Any ideas about that ? Thanks in advance, Kate -- Kup wlasne mieszkanie za 72 tys. zl. Sprawdz najlepsze oferty http://link.interia.pl/f25a8 - 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
RE: Webapp slow down after idle - 5.5.x
From: klin...@poczta.fm [mailto:klin...@poczta.fm] Subject: Webapp slow down after idle - 5.5.x The problem is that every first request after a longer idle (like a day) is served very slow. Sounds like the OS might be paging out Tomcat, and taking a long time to get all the necessary pages back in when a request is made. I'm not familiar with operational details of AIX, but I would suspect there are some system-level monitoring tools available to see if there is a paging spike in this situation. - Chuck THIS COMMUNICATION MAY CONTAIN CONFIDENTIAL AND/OR OTHERWISE PROPRIETARY MATERIAL and is thus for use only by the intended recipient. If you received this in error, please contact the sender and delete the e-mail and its attachments from all computers.
Re: Webapp slow down after idle - 5.5.x
On 22 February 2010 19:07, Caldarale, Charles R chuck.caldar...@unisys.com wrote: Sounds like the OS might be paging out Tomcat, and taking a long time to get all the necessary pages back in when a request is made. I'm not familiar with operational details of AIX, but I would suspect there are some system-level monitoring tools available to see if there is a paging spike in this situation. vmstat (http://publib.boulder.ibm.com/infocenter/aix/v6r1/index.jsp?topic=/com.ibm.aix.cmds/doc/aixcmds6/vmstat.htm) would do the job. No finesse, but sufficient information :-). - Peter - To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
