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!
Related
I have been trying to understand what is the cause of high memory usage from processes in the windows server I have. I installed that tool DebugDiag 1.2 to try to find the problem.
Here is what runs in my server:
I have the IIS server which has a decent number of pool applications (68 pool applications). For each pool application there are at least 4 applications.
Recently, I have faced problems related to high memory usage, causing the server to work at 97% of memory usage or higher.
It was working fine when I took this printscreen below. However, the memory usage will easily get higher.
Task Manager:
With that being said, I have been trying to understand how to use the tool "DebugDiag1.2" from microsoft to find something (part of the source code, an sql procedure) that might help me locate what is causing the problem.
I read that we can't limit the memory for each IIS pool application, so I guess the solution would be trying to optmize the application. But first I need to know where to start.
I hope someone can help me out.
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 I have been monitoring my heap memory using Java VisualVM, jconsole and Oracle Java Mission Control(I know it's outdated).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
I've started using ravenDb not too long ago, but I've noticed, that after installation, the ravenDb process is evenly getting higher memory usage (increasing around 0.1MB in a second).
If I leave my computer for a longer period of time - the process builds up with a high usage of memory.
I am not hosting any databases at all (clean reinstall), just using plain ravenDb installation as a windows service.
What could be causing this and how can I avoid it?
I have a web site and I am using iis as my web server. I noticed that on production server, the cpu reaches 95% usage pretty fast with very little users. this behaviour I don't see on my developement server. I am using visual studio to develop and iis as my local web server as well.
How much big traffic you have on production comparing to development server? How their parameters compare? Before starting a deep analysis of the application itself, I would identify all the infrastructure and environmental differences. Sometime such problems happens because of some other software, like antivirus software running in the background...
Nevertheless, because it sounds rather as a application problem, I would first check Event Viewer for errors. Then I would start from monitoring a few Performance Counters to correlate % Processor Time counter with Current Connections, Available Memory, # of Exceps Thrown / sec, % Time in GC and so on. This kind of behavior usually has a reason from the list:
excessive loops usage due to some logic error, like calling the same service again and again, trying to load or parse malfunctioned file etc. This can be analyzed with dump analysis (look below).
high CPU usage due to Garbage Collector - when memory usage is extensive (or there is a memory leak even) GC may start to consume more and more CPU fighting with the memory shortage. You will see this with memory-related performance counters.
a considerable amount of exceptions thrown (for example due to some environmental problems like network unavailability, production data difference) can also consume a lot of CPU. Event Viewer and exception-related performance counters (as they can be handled silently by your application) should be a indicator here.
To further analyze your application, I suggest to make a full memory dump during high CPU usage. You can do that with Debug Diag tool. Please refer this IIS troubleshooting guide for details.
Every night my IIS hangs with 3 w3wp.exe processen in the task manager list. It is not possible to kill the w3wp task using the most memory. Not even iisreset helps. I have to reboot the machince to get rid of the w3wp prosess.
Any suggestions?
Added: I have reduced the maxmemory of the default app pool to 120, but still the process goes above 200mb.
In the app-pool, set a limit on memory use, that will restart the app. when it uses too much memory. Might help.
From the screen shot, I cannot see problems such as high CPU utilization or huge memory usage.
You can learn how to use Debug Diagnostics to capture a hang dump and then analyse the dump with Debug Diagnostics. Its report should provide you some hints.
http://www.microsoft.com/downloadS/details.aspx?FamilyID=28bd5941-c458-46f1-b24d-f60151d875a3&displaylang=en
If you cannot do that yourself, I suggest you contact our Microsoft Support team.
I did not find a permament solution to my problem, but when i removed some web sites from my vps and reduced the max memory allowed for the default app pool the situation improved. I also removed the admin website which ran under its own appPool.