Out of Memory Error - Production Down

Question

Hi there:
Production environment setup:
JRUN Version 3.1.15506 Professional
OS Windows2000, 2Gb RAM
JRE 1.3.1_05
3 applications written in Java with JSP front end interfaces running on IIS
We have a situation that our javaw process associated to our JSP apps will error out with JavaOutOfMemory, and our users get the '500 HTTP Internal Server Error'. So far, we have performed the following tasks to resolve this problem:
1) Java code analysis (ensuring un-used objects' memories are marked for gc).
2) We have specified the heap sizes (-Xms 256M, -Xmx512M) and (-Xincgc) as a part of the Java parameter.
All of our efforts still cannot prevent this problem from recurring. We have also implemented -verbose:gc to generate the output. Our appls will run fine until the output shows back to back FULL GC, and the live object sizes remained unchange. (see below of our output file sample)
[GC 475473K->475430K(502528K), 0.1879665 secs]
[GC 475558K->475533K(502656K), 0.1820402 secs]
[Full GC 475579K->458333K(480448K), 13.8025016 secs]
[Full GC 458333K->458316K(480320K), 13.1841613 secs]
[GC 458380K->458325K(480320K), 9.5699595 secs]
[Full GC 458401K->458304K(480320K), 12.7683476 secs]
[Full GC 458304K->458303K(480320K), 12.6187116 secs]
[GC 458305K->458304K(480320K), 9.5906711 secs]
[Full GC 458574K->458313K(480320K), 12.6526716 secs]
[Full GC 458313K->458301K(480320K), 12.3069702 secs]
[GC 458349K->458303K(480384K), 9.3841784 secs]
[Full GC 458331K->458286K(480384K), 12.3653659 secs]
[Full GC 458286K->458285K(480320K), 12.2920750 secs]
[GC 458400K->458297K(480384K), 9.2735958 secs]
[Full GC 458450K->458315K(480384K), 12.4419648 secs]
[Full GC 458315K->458303K(480384K), 12.5853938 secs]
[GC 458481K->458311K(480384K), 9.5728288 secs]
[Full GC 458315K->458215K(480320K), 13.0953606 secs]
[Full GC 458215K->458214K(480320K), 12.5852260 secs]
Any advise or hint on finding a resolution?
Sincerely, Joseph C. Yin
[email protected]

Answer 1

If you are getting an out of memory error then it generally means you are running out of memory.
Now if you have no leaks in the system then it means that your load is too high for the resources that you are allocating. You either increase the resources or you throttle the system so it can't run out.
Since you profiled the application under load, it should not be possible for it to be a leak in java. It could be a leak in the JVM. If it is then you have to reduce to the problem, report it as a bug, and then try to find a work around.