Question

I have created my c# console application as windows service and installed the service in remote server which is 32 bit machine and has 2GB RAM.
To this server application many clients are connected and gets the data from server.
The problem is sometimes the server machine is down and unable to access the data, that time we need to restart the server every time.I have not able to identify where exactly the problem is.
When i was checking the evenlogs in server machine i found the below exception,

source .net 2.0 runtime error.

EventType clr20r3, P1 myapplication.exe, P2 1.3.2.1, P3 4cb724a3, P4 mscorlib, P5 2.0.0.0, P6 4be90358, P7 1947, P8 7, P9 system.outofmemoryexception, P10 NIL.

I have googled a lot, but unable to find exact reason.
I am using HTTPSERVER.MVC (opensource) for url communication.
To create service below code is added in the main function.

 ServiceBase[] ServicesToRun;
 ServicesToRun = new ServiceBase[] 
 { 
   new TouchService() 
  };
 ServiceBase.Run(ServicesToRun);

Please some one help me out.
Thanks in advance

Answer 1

The reason is – you are out of memory.

In .Net this doesn’t necessarily mean that there is physically no more memory, it just means that the CLR was unable to find enough contiguous memory to allocate something. This can be due to huge amounts of memory already being allocated, or due to memory fragmentation.

Without knowing more about your application it is difficult to give more than general advice, but a few pointers are:

• try monitoring the size of the heaps using the Windows performance counters and tools such as Process Monitor
• look at your code – are you holding on to references indefinitely and growing the overall size of memory being used without end?
• are you allocating any large single blocks of memory above about 80KB, for example large strings of data? Large objects like this are allocated on the Large Object Heap and not compacted which can lead to fragmentation and OutOfMemoryExceptions?
• Have you tried using a memory profiler? (I tend to use SciTech’s .Net Memory Profiler, but there are other good ones). This lets you start your service and attach the profiler, do some work, take a snapshot, do some more work, and then look at the differences between the snapshots. This is a very powerful way of spotting if and why memory usage is creeping up.
• Are you doing lots of XML serialization? Apart from the propensity to generate large strings (see previous point), using certain overloads on the XmlSerializer constructor can also cause new xml serialization dlls to get generated and loaded into the application pool every time they are used.

These are just some random thoughts, but I would suggest getting a basic understanding of CLR memory management and garbage collection if you don’t already, try some monitoring and profiling, and take a critical look at your code.