Tomcat Hang on Linux (hangs the entire system)
Hi there, I am posting this in a few areas because I cannot pinpoint where the problem stems from. I have a standard Pentium III bases pc running linux. It has only 380 meg (or therabouts) of ram Using IBM JVM 1.4.1 and tomcat 4.1.18 (I know there are later version, but they all hang) I have 2 webapps running. One of them uses Apache to translate two different domain to the right ibay for it's content but uses the same code base. The second webapp is accessed, currently, using http://www.mycomapny.com:8080/MyApp style URL. The webapp just hangs. It will not load any pages, and when it hangs, both webapps hang. So I think this is a Tomcat or Java or Linux error. Once the hang occurs I cannot do a ps -ef as this also hangs. My only option is to reboot the machine. But it hangs half way and has to be physically powered off. We are going to put a new, more powerful computer in there, but for now I wanted to see if anyone else had experienced such a problem. Can you give me some pointers as to where to look for the source of the problem. This has happened before, and I got no information about it. I know it's a pretty vague explanation, but I don't know what more informationI can give you. The log files do not show any errors, and it never happens at the same point in the web application. At first I thought it happen when concurrent users logged in, but that's not the case either, and I have trimmed down the sychornicity management when accesing Singletons in my web app. Now I have been through all my code, and cannot find anything that should be causing an error. I have run the code under a number of different cirsumstances on my development machine (Windows 2000) and everything runs without a problem. Any help would be appreciated Regards Steve
Re: Tomcat Hang on Linux (hangs the entire system)
It might be a hardware related problem. Try to change the memory. Viorel Dragomir . .. --- - Original Message - From: Steve Vanspall To: tomcat-user@jakarta.apache.org Sent: Thursday, March 31, 2005 09:38 Subject: Tomcat Hang on Linux (hangs the entire system) Hi there, I am posting this in a few areas because I cannot pinpoint where the problem stems from. I have a standard Pentium III bases pc running linux. It has only 380 meg (or therabouts) of ram Using IBM JVM 1.4.1 and tomcat 4.1.18 (I know there are later version, but they all hang) I have 2 webapps running. One of them uses Apache to translate two different domain to the right ibay for it's content but uses the same code base. The second webapp is accessed, currently, using http://www.mycomapny.com:8080/MyApp style URL. The webapp just hangs. It will not load any pages, and when it hangs, both webapps hang. So I think this is a Tomcat or Java or Linux error. Once the hang occurs I cannot do a ps -ef as this also hangs. My only option is to reboot the machine. But it hangs half way and has to be physically powered off. We are going to put a new, more powerful computer in there, but for now I wanted to see if anyone else had experienced such a problem. Can you give me some pointers as to where to look for the source of the problem. This has happened before, and I got no information about it. I know it's a pretty vague explanation, but I don't know what more informationI can give you. The log files do not show any errors, and it never happens at the same point in the web application. At first I thought it happen when concurrent users logged in, but that's not the case either, and I have trimmed down the sychornicity management when accesing Singletons in my web app. Now I have been through all my code, and cannot find anything that should be causing an error. I have run the code under a number of different cirsumstances on my development machine (Windows 2000) and everything runs without a problem. Any help would be appreciated Regards Steve
Re: Tomcat Hang on Linux (hangs the entire system)
Check your RAM, might be bad Drew. On Wed, 2005-03-30 at 23:38, Steve Vanspall wrote: > Hi there, > > I am posting this in a few areas because I cannot pinpoint where the > > problem stems from. > > I have a standard Pentium III bases pc running linux. > > It has only 380 meg (or therabouts) of ram > > Using IBM JVM 1.4.1 and tomcat 4.1.18 (I know there are later version, but > > they all hang) > > I have 2 webapps running. One of them uses Apache to translate two > > different domain to the right ibay for it's content but uses the same code > > base. The second webapp is accessed, currently, using > > http://www.mycomapny.com:8080/MyApp style URL. > > The webapp just hangs. It will not load any pages, and when it hangs, both > > webapps hang. So I think this is a Tomcat or Java or Linux error. Once the > > hang occurs I cannot do a ps -ef as this also hangs. My only option is to > > reboot the machine. But it hangs half way and has to be physically powered > > off. We are going to put a new, more powerful computer in there, but for > > now I wanted to see if anyone else had experienced such a problem. Can > > you give me some pointers as to where to look for the source of the > > problem. > > This has happened before, and I got no information about it. I know it's a > > pretty vague explanation, but I don't know what more informationI can give > > you. > > The log files do not show any errors, and it never happens at the same > > point > > in the web application. At first I thought it happen when concurrent users > > logged in, but that's not the case either, and I have trimmed down the > > sychornicity management when accesing Singletons in my web app. > > Now I have been through all my code, and cannot find anything that should > > be causing an error. I have run the code under a number of different > > cirsumstances on my development machine (Windows 2000) and > > everything runs without a problem. > > Any help would be appreciated > > Regards > > Steve > - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Tomcat Hang on Linux (hangs the entire system)
Hi, You can try the following step by step approach 1) Check whether you are able to run the examples application in tomcat. If you are not able to run that there's a problem with tomcat configuration or the JVM. 2) If that runs smoothly without any problems, check your application and ensure that it doesn't go into any infinite loops etc, since that's one runaway thing that can bring down the whole machine consuming lot of cpu and perhaps even memory leaving no room for anything else. 3) If your application is OK, make sure no other application is consuming lot of CPU or memory. -- Original Message -- On 31 Mar 2005, 04:43:10 PM, Viorel Dragomir writes: > > It might be a hardware related problem. > Try to change the memory. > > > > > Viorel Dragomir > > . > .. > --- > > > > - Original Message - > From: Steve Vanspall > To: tomcat-user@jakarta.apache.org > Sent: Thursday, March 31, 2005 09:38 > Subject: Tomcat Hang on Linux (hangs the entire system) > > > Hi there, > > I am posting this in a few areas because I cannot pinpoint where the > > problem stems from. > > I have a standard Pentium III bases pc running linux. > > It has only 380 meg (or therabouts) of ram > > Using IBM JVM 1.4.1 and tomcat 4.1.18 (I know there are later version, but > > they all hang) > > I have 2 webapps running. One of them uses Apache to translate two > > different domain to the right ibay for it's content but uses the same code > > base. The second webapp is accessed, currently, using > > http://www.mycomapny.com:8080/MyApp style URL. > > The webapp just hangs. It will not load any pages, and when it hangs, both > > webapps hang. So I think this is a Tomcat or Java or Linux error. Once the > > hang occurs I cannot do a ps -ef as this also hangs. My only option is to > > reboot the machine. But it hangs half way and has to be physically powered > > off. We are going to put a new, more powerful computer in there, but for > > now I wanted to see if anyone else had experienced such a problem. Can > > you give me some pointers as to where to look for the source of the > > problem. > > This has happened before, and I got no information about it. I know it's a > > pretty vague explanation, but I don't know what more informationI can give > > you. > > The log files do not show any errors, and it never happens at the same > > point > > in the web application. At first I thought it happen when concurrent users > > logged in, but that's not the case either, and I have trimmed down the > > sychornicity management when accesing Singletons in my web app. > > Now I have been through all my code, and cannot find anything that should > > be causing an error. I have run the code under a number of different > > cirsumstances on my development machine (Windows 2000) and > > everything runs without a problem. > > Any help would be appreciated > > Regards > > Steve > > > - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: Tomcat Hang on Linux (hangs the entire system)
Hi, One thing I have found helpful in the past is to looks at sar statistics leading up to a system lockup. If it doesn't occur too quickly you might catch something building up on the system. You must have the sysstat package installed. See man sar. I check things like process creation, memory, swapping, etc. Jim T. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Thursday, March 31, 2005 1:44 AM To: Tomcat Users List Subject: Re: Tomcat Hang on Linux (hangs the entire system) Hi, You can try the following step by step approach 1) Check whether you are able to run the examples application in tomcat. If you are not able to run that there's a problem with tomcat configuration or the JVM. 2) If that runs smoothly without any problems, check your application and ensure that it doesn't go into any infinite loops etc, since that's one runaway thing that can bring down the whole machine consuming lot of cpu and perhaps even memory leaving no room for anything else. 3) If your application is OK, make sure no other application is consuming lot of CPU or memory. -- Original Message -- On 31 Mar 2005, 04:43:10 PM, Viorel Dragomir writes: > > It might be a hardware related problem. > Try to change the memory. > > > > > Viorel Dragomir > > . > .. > --- > > > > - Original Message - > From: Steve Vanspall > To: tomcat-user@jakarta.apache.org > Sent: Thursday, March 31, 2005 09:38 > Subject: Tomcat Hang on Linux (hangs the entire system) > > > Hi there, > > I am posting this in a few areas because I cannot pinpoint where the > > problem stems from. > > I have a standard Pentium III bases pc running linux. > > It has only 380 meg (or therabouts) of ram > > Using IBM JVM 1.4.1 and tomcat 4.1.18 (I know there are later version, but > > they all hang) > > I have 2 webapps running. One of them uses Apache to translate two > > different domain to the right ibay for it's content but uses the same code > > base. The second webapp is accessed, currently, using > > http://www.mycomapny.com:8080/MyApp style URL. > > The webapp just hangs. It will not load any pages, and when it hangs, both > > webapps hang. So I think this is a Tomcat or Java or Linux error. Once the > > hang occurs I cannot do a ps -ef as this also hangs. My only option is to > > reboot the machine. But it hangs half way and has to be physically powered > > off. We are going to put a new, more powerful computer in there, but for > > now I wanted to see if anyone else had experienced such a problem. Can > > you give me some pointers as to where to look for the source of the > > problem. > > This has happened before, and I got no information about it. I know it's a > > pretty vague explanation, but I don't know what more informationI can give > > you. > > The log files do not show any errors, and it never happens at the same > > point > > in the web application. At first I thought it happen when concurrent users > > logged in, but that's not the case either, and I have trimmed down the > > sychornicity management when accesing Singletons in my web app. > > Now I have been through all my code, and cannot find anything that should > > be causing an error. I have run the code under a number of different > > cirsumstances on my development machine (Windows 2000) and > > everything runs without a problem. > > Any help would be appreciated > > Regards > > Steve > > > - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
[OT] RE: Tomcat Hang on Linux (hangs the entire system)
[Marked off-topic as almost certainly not directly Tomcat-related] > From: Steve Vanspall [mailto:[EMAIL PROTECTED] > My only option is to reboot the machine. > But it hangs half way and has to be physically powered off. As others have suggested, this may well be bad RAM - or I've had similar symptoms with two motherboards (from different manufacturers) that were OK at low bus speeds but on the edge at specced speed. The RAM is the more likely issue. I suggest downloading and booting with Memtest86+ (http://www.memtest.org/) as a first test. Plan to leave it running for several hours. It will log any errors it finds in the lower part of the screen. A second test is to run cpuburn (http://pages.sbcglobal.net/redelm/). cpuburn itself is a useful test, but I strongly recommend running burnbx and burnmmx for a few minutes each with each of their 'E' and 'L' parameters - E and L exercise L2 cache and RAM respectively. These will run while the machine is up. If they exit unexpectedly, or the machine spontaneously restarts, you've found your culprit! - Peter - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
