How to tell GC to clean embedded object as well?

Question

We have an event class which has a reference of a MsgBody class:

public class StatusEvent
{
   MsgBody msgBody;
   public StatusEvent(MsgBody body)
   {
       msgBody = body;
   }
....
}

public class MsgBody
{
   string s1;
   string s2;
.....

}

MsgBody class is ONLY used by StatusEvent. No other place a MsgBody is refered. When a StatusEvent instance is created, a MsgBody instance will be created. When a StatusEvent object is ready for cleanup, a MsgBody object will be safe to be cleanup.

But the result is the MsgBody cleanup is way behind the StatusEvent. From one profiler result, I found there ware only 43 Live instances of StatusEvent but there were 9,940 instances of MsgBody!

Is there a way to link them together and make GC cleanup MsgBody when it wipe StatusEvent away?

thanks,

Answer 1

If you want deterministic release of resources, StatusEvent needs to implement IDisposable. In the IDisposable.Dispose method implementation, you can release all the resources held. In your case you can put the statement msgBody = null; to your code.

Are you sure there is no other place where msgBody is being stored?

Answer 2

Normally the GC should automatically free the memory as soon as the memory is needed anywhere else. But if you want to speed this up, you can call the following to free memory immidiately:

http://msdn.microsoft.com/en-us/library/system.gc.collect.aspx

Answer 3

If the MsgBody does not have any expensive resource access, then the GC will take care once the object is out of scope. Aditionally you can set msgBody=null;.

Answer 4

If you don't call GC.Collect(), so it would totally depend on GC. I don't think there's the way to instruct GC in the manner you want.