I've been having trouble with my webapp. My heap memory peak up to nearly to max size for about 30 mins and the it crashes my system.
I have googled and tried nearly everything. I have been monitoring my heap memory using Java VisualVM, jconsole and Oracle Java Mission Control(I know it's outdated).
So what I have tried until know:
Monitored heap memory to see if there is a specific thread running at specific time and it peak the memory. (This is not the case as it doesn't specifically peak at specific times.)
2.Increased my heap memory size.
Followed instructions from:
http://karunsubramanian.com/websphere/top-4-java-heap-related-issues-and-how-to-fix-them/
So my questions are:
Is there any tool that can help me see if I have a memory leak and from where?
Has anyone experienced the same issue.
Any pointers on how to manage this kind of problems.
Btw I am quite new in this area so please be kind.
Tomcat 7 on Windows Server 2012
JAVA 7
If you need more information please comment.
You need to configure the jvm to create a heapdump when an outofmemory occurs.
-XX:+HeapDumpOnOutOfMemoryError
Then analyze the heap dump to find what classes are using the memory
Related
I'm running Node.js on a server with only 512MB of RAM. The problem is when I run a script, it will be killed due to out of memory.
By default the Node.js memory limit is 512MB. So I think using --max-old-space-size is useless.
Follows the content of /var/log/syslog:
Oct 7 09:24:42 ubuntu-user kernel: [72604.230204] Out of memory: Kill process 6422 (node) score 774 or sacrifice child
Oct 7 09:24:42 ubuntu-user kernel: [72604.230351] Killed process 6422 (node) total-vm:1575132kB, anon-rss:396268kB, file-rss:0kB
Is there a way to get rid of out of memory without upgrading the memory? (like using persistent storage as additional RAM)
Update:
It's a scraper which uses node module request and cheerio. When it runs, it will open hundreds or thousands of webpage (but not in parallel)
If you're giving Node access to every last megabyte of the available 512, and it's still not enough, then there's 2 ways forward:
Reduce the memory requirements of your program. This may or may not be possible. If you want help with this, you should post another question detailing your functionality and memory usage.
Get more memory for your server. 512mb is not much, especially if you're running other services (such as databases or message queues) which require in-memory storage.
There is the 3rd possibility of using swap space (disk storage that acts as a memory backup), but this will have a strong impact on performance. If you still want it, Google how to set this up for your operating system, there's a lot of articles on the topic. This is OS configuration, not Node's.
Old question, but may be this answer will help people. Using --max-old-space-size is not useless.
Before Nodejs 12, versions have an heap memory size that depends on the OS (32 or 64 bits). So, following documentations, on 64-bit machines that (the old generation alone) would be 1400 MB, far away from your 512mb.
From Nodejs12, heap size take care of system RAM; however Nodejs' heap isn't the only thing in memory, especially if your server isn't dedicated to it. So set the --max-old-space-size permit to have a limit regarding the old memory heap, and if your application comes closer, the garbage collector will be triggered and will try to free memory.
I've write a post about how I've observed this: https://loadteststories.com/nodejs-kubernetes-an-oom-serial-killer-story/
my application is running on jboss 6.1, and after few days my applications runs very slow., this is the situation I am facing every week,. for this I am killing java and clearing the temp and work folders and restarting the jboss again. Is there any other ways to clean the memory / manage the application. Kindly give me the suggestions for Linux and windows platforms.
Kindly help any one.
Thanks & Regards,
Sharath
Based on your RAM size of the system you can increase following parameters in run.conf(for linux) or run.conf.bat(for windows):
XMS, XMX, MaxPermSize.
-Xms512M -Xmx1024M -XX:MaxPermSize=128M
The flag Xmx specifies the maximum memory allocation pool for a Java Virtual Machine (JVM), while Xms specifies the initial memory allocation pool.
MaxPermSize are used to set size for Permanent Generation
The Permanent Generation is where class files are kept. These are the result of compiled classes and jsp pages. If this space is full, it triggers a Full Garbage Collection. If the Full Garbage Collection cannot clean out old unreferenced classes and there is no room left to expand the Permanent Space, an Out‐of‐ Memory error (OOME) is thrown and the JVM will crash
Hope you are aware of these three flags.
I am getting the error SEVERE: java.lang.OutOfMemoryError: Java heap space for my OpenShift application. As the error suggests I need to increase the java heap space. I have tried ssh'ing into my open-shift server and executed set JAVA_OPTS=-Xms1024M -Xmx1024M. Although the error is still present.
I am deploying a .war file on a tomcat7 server.
What should I be doing instead to fix this problem?
What size gear are yo using? If it is the small gear on the free account you only get 512MB of memory to begin with. If you need more memory you will need to upgrade to a larger gear, see http://www.openshift.com/pricing for how much memory the larger gear sizes have.
First, you need to check the heap size of the existing java process
Second, you need to try and increase it using the JAVA_OPTS option or otherwise. After making the change, check the process to validate that it indeed increased the heap size
Finally, if bumping the heap does not help, then as suggested you will need to perform some level of profiling or use some other technique to troubleshoot.
I have a web application that is eventually running out of memory when it runs on IIS 7 Windows Server 2008. When I attempt to run a memory profiler against the application to determine the leak, it is not reproducible on my development workstation...Windows Vista.
The GC collection cycles are not consistent between the server and the workstation and it appears the server's collection is not reclaiming all of its memory and is eventually running out. The server becomes non responsive and throws out of memory exceptions.
We have tried setting objects that are surviving too many generations to null...Some improvement was noticed.
Any assistance/recommendations would be greatly appreciated
Tess Ferrandez's blog has some great information on debugging memory leaks using Windbg.
By taking a dump of the running application and then analysing it in Windbg, you should be able to find the source of the leaks you are seeing.
The following entries are probably a good starting point:
Setup (including links to configuring Windbg
Memory Leak Lab 1
Memory Leak Lab 2
Good luck!
I have openfire installed on my debian server.
I want to know that whether openfire java memory should be less than server memory?
For e.g. i have a server with 256 MB RAM now can i have openfire java memory more than 256 MB RAM or it should be less than 256.
Please help
Thanks,
Pankaj
"Java memory" should definitely be lower, preferably quite a bit lower than available RAM, otherwise your server will start swapping and server performance go down a lot.
A number of things to consider to determine the "right" settings for Java heap space:
what's running on the server? If OpenFire is the only thing running, it can obviously be allowed to reserve more RAM
how much RAM does OpenFire really need? If you give a Java process lots of heap memory, it'll fill it before initiating a garbage collection. If you decrease heap size, it'll just have to collect garbage more often.
It may take some time to find the "ideal" settings, but often it's not useful to just allow the server to take up more memory.