Archive for May, 2008

Strange tomcat threading behavior

Published at May 2, 2008 in . 4 Comments

We are having some threading issues while load testing our production tomcat servers. When I fire up JMeter and hit it with about 50 users, tomcat grabs a ton of threads. Eventually this causes some instability and tomcat hangs.

The weird thing is I can’t duplicate it locally. I hit my local running instance and it might grab a few more threads which is to be expected, but not skyrocket up. At first I thought it was a problem with iBatis which had a known threading issue. But after upgrading to the latest beta it hasn’t solved anything. I also switched to using the session API in iBatis as well to no avail.

My gut tells me it isn’t directly tomcat’s fault since I can’t reproduce it and I don’t want to give up on tomcat just yet. However this problem is really keeping us from ramping up traffic on our beta site which of course doesn’t make the brass too thrilled.

In both cases tomcat is configured to use the APR connector and maxThreads are set at about 150. The only real difference in the configs is that production is in a cluster and is using large memory page configurations. Our production boxes have 16gb of RAM and 8 cores, so it the hardware has a lot of room to go.

Anyone have any thoughts about what is causing this?

Twitter abandoning RoR?

Published at May 2, 2008 in and . 0 Comments

After the much publicized leaving of Blaine Cook and Twitter’s continued stability and scalability problems, now there is talk of Twitter dropping Rails and moving to either Java or (GASP!!) PHP.

Either one wouldn’t bother me. PHP is known to power some really big sites, like Digg for example, and Java does as well. The funny thing is if they choose PHP it would REALLY piss off the Ruby crowd. In professional circles PHP is seen as bottom of the barrel almost down there with VB.

What would be really cool to see was if they chose Grails as an alternative. Talk about a feather in the cap for the Grails crowd…