from my side, it's http server configuration limitation.After peformance tune, it works well now.
On Tue, Mar 3, 2009 at 10:10 PM, Stella Lok <oinvertedwo...@gmail.com>wrote: > Hi, > > After > doing much testing, I am able to recreate the "frozen server" > situation on demand. > > Strangely enough, it seems like the problem is caused by my use of > org.apache.commons.lang.builder.ToStringBuilder in a (non-infinite) > loop. When I remove the usage, the problem disappears. I'll have to do > more investigation before I can reach a conclusion though > > On Fri, Feb 27, 2009 at 12:42 AM, Stella Lok <oinvertedwo...@gmail.com> > wrote: > > Hi Kevan, > > > > The machine has one Xeon processor which is a dual core. I am running > > WAS CE on IBM JSE 5. > > > > I do have the thread dump showing the blocked MQ threads, which I have > > just forwarded to you, if you would like to take a look (if anyone > > else is interested in taking a look, please let me know) > > > > Btw, the activemq used is not the one embedded in WASCE, but an external > one. > > > > Thank you very much > > > > On Thu, Feb 26, 2009 at 11:13 PM, Kevan Miller <kevan.mil...@gmail.com> > wrote: > >> > >> On Feb 26, 2009, at 5:58 AM, Stella Lok wrote: > >> > >>> Hi, > >>> > >>> I am using WAS CE 2.0.0.2 with ActiveMQ 5.2.0. While doing load > >>> testing, I encountered situations when the web server (which is the > >>> Tomcat embedded in WAS CE) permanently (until restart) stopped > >>> responding to any HTTP requests (the catalina log stops logging new > >>> requests), and none of the apps nor the admin console can be accessed > >>> anymore. When that happens, the WAS CE java process' CPU utilization > >>> would invariably be permanently stuck at around the 50% level, even if > >>> I completely stop accessing the server. > >>> > >>> I did a thread dump whenever this occurred, and most of the time I do > >>> not see any blocked threads, only runnable, parked and > >>> waiting-on-condition threads. Once, I was able to see that there were > >>> 4 blocked ActiveMQ threads, though I'm not sure if this is related. > >>> > >>> I would be most grateful if someone could help guide me to possible > >>> causes of the problem. > >> > >> Hmm. Do you still have the thread dumps? Esp. the one showing the > blocked > >> AMQ threads? Is this a 2 CPU machine (e.g. a single dual core > processor?) > >> Sounds like you have a single thread spinning. A thread dump should help > >> identify the culprit... Are you running on Sun or IBM JSE? > >> > >> --kevan > >> > > > -- viola
