Clearing up some confusion over finalization and other areas in GC

GC and Finalization

Avnrao's Blog — Fri, 05 Nov 2004 11:49:00 GMT

GC and Finalization

OTC Links For November 6

OdeToCode Link Blog — Sun, 07 Nov 2004 03:39:00 GMT

Maoni:Clearing up some confusion over finalization and other areas in GC

Sam Gentile's Blog — Mon, 08 Nov 2004 19:02:00 GMT

Just like your Mother: The Garbage Collector

Jason Alexander's Site — Tue, 09 Nov 2004 06:12:00 GMT

Maoni:Clearing up some confusion over finalization and other areas in GC

Sam Gentile's Blog — Tue, 09 Nov 2004 17:39:00 GMT

New and Notable 68

Sam Gentile's Blog — Tue, 21 Dec 2004 14:33:00 GMT

New and Notable 68

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Special threads in CLR

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Question: How many threads does a typical managed process have when it just starts to run?&nbsp;&nbsp;...

Garbage Collection Articles: an updated list

Steve Hebert's Development Blog — Wed, 27 Jul 2005 00:52:28 GMT

I previously blogged about a set must-read garbage collection articles&nbsp;and issues around directly...

How many threads does a typical managed process have when it just starts to run?

C#, VS Deployment and all geek talk — Thu, 18 Aug 2005 19:33:08 GMT

Special threads in CLR

Yun Jin's WebLog — Sun, 28 Aug 2005 22:44:56 GMT

Question: How many threads does a typical managed process have when it just starts to run?&nbsp;&nbsp;...

re: Clearing up some confusion over finalization and other areas in GC

... — Mon, 12 Mar 2007 09:23:10 GMT

Nice site you have!

re: Clearing up some confusion over finalization and other areas in GC

... — Fri, 16 Mar 2007 23:58:18 GMT

pagine piuttosto informative, piacevoli =)

Top 20 .NET Garbage Collection (GC) Articles

roy ashbrook — Fri, 22 Jun 2007 07:40:53 GMT

Ah. Garbage Collection... how I love and hate thee. =P I think one sad thing about programming in .net

Top 20 .NET Garbage Collection (GC) Articles

roy ashbrook — Fri, 22 Jun 2007 07:43:05 GMT

Ah. Garbage Collection... how I love and hate thee. =P I think one sad thing about programming in .net

Dispose Pattern and Object Lifetime [Brian Grunkemeyer]

Noticias externas — Tue, 30 Oct 2007 19:00:18 GMT

The Dispose pattern is the way to think of object lifetime in the .NET Framework. Admittedly, it can

The Achilles Thread

Andreas Zenker - My OBJECTive Opinion — Mon, 19 Nov 2007 05:42:26 GMT

"[when debugging] If you see hoof prints think horses, not zebras". Hunt and Thomas, in The Pragmatic...

[??????]??????Top 20 .NET Garbage Collection (GC) ?????? : ????????????????????? TAHETA.ORG

Tue, 23 Dec 2008 15:43:37 GMT

PingBack from http://www.taheta.org/?p=94

When is Finalize called? | keyongtech

When is Finalize called? | keyongtech — Thu, 22 Jan 2009 04:35:08 GMT

PingBack from http://www.keyongtech.com/451497-when-is-finalize-called

Performance Issue Caused by Crashed Finalizer Thread

AsiaTech: Learning by Practice — Mon, 06 Apr 2009 05:19:02 GMT

Customer had a newly developed .NET web application hosted in IIS 6. They recently experienced some performance

Finalization is only for releasing managed resources?

Adam M. — Tue, 07 Jul 2009 02:29:47 GMT

Hi Maoni,

I had two questions. First, you said several times that finalization is only for releasing unmanaged resources.

I've been in the habit of making objects finalizable if they hold references to IDisposable objects. Then if they get finalized, they'll call the .Dispose() methods of the objects they reference.

This isn't directly releasing unmanaged resources, but rather disposing managed resources that I assume release some unmanaged resources somewhere down the line. (For instance, I may have a type Big, which is finalizable and uses a large unmanaged buffer, and Small, which uses an instance of Big. So I would make Small finalizable too to dispose the Big inside of it.)

After reading your blog, I'm wondering if that's a bad idea. Maybe if they're allocated at similar times, then they would be collected at the same time, and so it's needlessly increasing the number of finalizable objects? On the other hand, Small being finalizable to free up Big is similar to Small being finalizable to free up a FileStream (but still different in one important way -- Big only consumes unmanaged memory but FileStream keeps a file open).

In short, can you elaborate on exactly which situations benefit from making a class finalizable, and which don't, and can you explain in more detail how finalizable objects impact GC performance? (I.e., what extra operations does it need to do if you create one more finalizable object?)

The second question is about how the GC handles circular references. I remember reading that it can handle them, and I generally haven't worried about them, but sometimes I've made an object disposable (maybe not finalizable) to break circular dependencies when it's related to event handlers. For instance A has a reference to B (a Timer, say) and A also uses an event handler on B (Timer.Tick), creating a reference from B -> Delegate -> A. How important is this kind of thing?

Thank you, and keep up the good work! :-)

-- Adam