Howdy, >The (4) production servers are running Solaris OS with 4CPU, 4GB RAM and >7GB of swap space. In all we have 12 tomcats and 4 Apaches. > >Each machine is equipped with one apache and 3 tomcats. > >The Database machines is also running Solaris with 16CPU's, 20 GB RAM >and 20GB swap space. > >We have apache (1.3.27) and tomcat(3.3) in our production servers with >JVM (1.4.2 recently upgraded). The frequent problems we face are:
I was surprised to see tomcat 3.x and apache 1.x with such massive hardware and elaborate setup. Any particular reason why you don't have more recent versions of tomcat and apache httpd? >- High GC (increased pause time when the NewSize=128m -ms=256m -mx=778m >and using the default LWP synchronization scheme with GC parameters >PrintGCDetails and Time Stamps to analyse in GCportal)(these setting are >for individual tomcats) You're doing -Xmx, -Xms, -XX:NewSize, right? Not exactly as you typed above. You should keep tuning to reduce your GC pause: the train (-Xincgc) or parallel collectors would probably be good for you. >- The Process running the JVM reached 1GB of size in the 'TOP' list >recently, which at this point had to be killed on one of the tomcats. If -Xmx=778m, that's the max heap. 778m is a strange number BTW: how did you arrive at that? Anyways, the output from top represents the whole JVM, i.e. heap + stack + symbols + OS overhead, so it's always more than the heap itself. However, a nearly 25% overhead (778mb->1024mb) is pretty wild. The difference between -Xmx and top when the heap is maxed out on Solaris is usually closer to 12-15%. >and sometime with high GC and CPU usage. The 3rd production machine >causes high number of thread due to High GC most of the times and on You have your causality mixed up here. High GC does not cause a high number of threads. >Once the database connections are high with an increased number of >threads, they are unable to come back to the normal condition and we >have to kill this tomcat as after some time when the load increases, Why are they unable to come back? Are they not released back into the pool? Do they go bad but not abandoned by the pool? >One last thing, there are some occasional tomcat death (JVM crashes) >once in a while. What are the crash messages? If they're internal JVM crashes (producing hs_err_[pid] files), make sure you have the latest Solaris patches required for your JDK. There are a bunch of them required for JDK 1.4.x. Yoav Shapira This e-mail, including any attachments, is a confidential business communication, and may contain information that is confidential, proprietary and/or privileged. This e-mail is intended only for the individual(s) to whom it is addressed, and may not be saved, copied, printed, disclosed or used by anyone else. If you are not the(an) intended recipient, please immediately delete this e-mail from your computer system and notify the sender. Thank you. --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
