Hello Matthew, Without wanting to advertise own product, I think moskito can help you a lot here. It was specially designed to detect cpu eaters among call trees. Feel free to contact me of list if you want to give it a try ;-)
http://moskito.anotheria.net/moskitodemo/mui/mskShowAllProducers regards Leon On Thu, Oct 16, 2008 at 10:30 PM, Matthew Laird <[EMAIL PROTECTED]> wrote: > We're pulling our hair out with a Tomcat issue. > > We have an in-house application running on Tomcat 5.5 with Sun JDK 1.6. > The machine is an x86 dual-CPU, quad core (8 cores total) with 16GB of > RAM. We're running OpenSuSE 10.2, 32-bit. Java memory size set to 2GB, > multi-threaded GC enabled. > > What occurs is when a user clicks a certain kind of analysis on the > website, data is retrieved from a database and then a lot of formatting > is done before returning it to the user. This typically causes 100% CPU > usage for this thread for a few minutes (bioinformatics application, > that part isn't going to change). > > Unfortunately what then occurs is all other threads suddenly become > unusably slow. The entire web application grinds to a halt until this > thread that's running hot completes. > > Looking at top, it appears that these threads aren't spreading among all > the cores. I see one core go to 100% usage, and the others stay at 100% > idle. So we're running multi-thread, but because everything is staying > on the same core, we're still getting thread contention that's bringing > the entire application to its knees. > > The only time I began to see the other cores actually start being used > is when I enabled multi-threaded GC. But that doesn't give much > improvement since the threads responding the web requests are still all > on the same core. > > I'm not sure how to convince the Tomcat/Java container to spread its > threads among the cores. > > Thanks. > > -- > Matthew Laird > Lead Software Developer, Bioinformatics > Brinkman Laboratory, MBB Dept. > Simon Fraser University > > > --------------------------------------------------------------------- > To start a new topic, e-mail: users@tomcat.apache.org > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > --------------------------------------------------------------------- To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
