Hello Subir Sengupta , If you are suspecting GC problem, you can always run the app thru any number of analyze tools, ( OptimizeIt ) for example.
If the reason for freeze up is GC, then you have a much bigger issue on your hands. B/c that is a lot of objects :) You might want to consider using loadbalancer for distributed type app. Issue Two: That sounds like a programmer error. I don't know how you have implemented object concurancy, but 99% of the type stale data is due to programmer error. I personally don't think that it is an i.e. issue since I.E. would not mix and match the data, it would display old data; Best Regards, Alex K. -----Original Message----- From: Subir Sengupta [mailto:[EMAIL PROTECTED]] Sent: Wednesday, January 08, 2003 5:51 PM To: 'Tomcat Users List' Subject: RE: Tomcat oddities Issue One: If Tomcat used up all your memory, you would see OutOfMemory exceptions being thrown, not a freeze. Do you see these? Everything will stop *while* GC is occurring (not until GC occurs). Have you tried increasing the amount of memory allocated to Java? Use the -Xms and -Xmx flags to set memory allocations. However, if you do have a memory leak, increasing the memory will simply increase the intervals between freezes. -----Original Message----- From: Michael Molloy [mailto:[EMAIL PROTECTED]] Sent: Wednesday, January 08, 2003 1:55 PM To: Tomcat Users List Subject: Tomcat oddities My company is in the deployment stage of a project that uses tomcat to serve information from an oracle database to about 25 people. When the app goes live, there will be about 150 people connected at any one time. Tomcat 4.1.12 is running behind Apache on Windows 2000 on a single cpu box, and Oracle is running on a separate Windows 2000 2-way box. (Windows was the client decision, not ours.) Issue One We're seeing two serious issues, the first of which happens about once a day, sometimes more. When there are several users on the system, maybe up to 15, there is a freeze during which no one can get any responses back from Tomcat. This period usually lasts from 5 to 15 minutes, after which the system returns to normal and everything zips along. We've tuned queries, so we don't think that is the problem. There may still be a rogue query out there causing problems, but we think it's unlikely. Besides, I don't know why that would stop everyone, which is what's happening. Another possibility that we've discussed is that tomcat is simply using all of the memory and everything basically stops until GC occurs. This seems the most likely to me, but I wanted to ask the group. I don't know what the page file size is, nor do we have access to the server so we can't check task manager. Can anyone think of any other possibilities? Issue Two We've had two reports where a user has had data from an old session show up in his/her current session. For example, I wrote a class that stores information from 14 different JSPs. The object is put into the user's session. In these two occasions, the user entered a new record using these screens & saved the data to the database. The user took an hour lunch break, which would have been long enough to timeout (set at 20 minutes), returned, and queried a different record. Some of the data from the previous record showed up in the holder class in his/her current session and was saved to the database. Any idea what that could be? The only thing I can think of is that IE is doing some data caching & mixing things up a bit. Any suggestions will be greatly appreciated. We really need to get this figured out quickly. Thanks --Michael Molloy -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]> -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]> -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
