No. When this happens, the server comes to a crawl. I can't attach a
debugger or do anything useful except shut down the COM+ app (even that
takes a few minutes to respond to the clicks). So I don't really know
what's going on.

John

"Anatoly" <wiretransfers (AT) yahoo (DOT) com> wrote

Mike,

It's the QueuedComponents sample
(FrameworkSDK\Samples\Technologies\ComponentServic es\QueuedComponents\CS).
I'm running it on Windows2000 Server SP4. My Framework is 1.0.3705. I
built and installed it without modification using the build.bat file.
Here's what it does for me:

Start the QCDemoSvr COM+ application
DLLHOST starts and takes 5,512k
If I just let it sit, after a few minutes this drops to 3,324k
Start QCDemo.exe
DLLHOST Memory increases to 3,360k
Click "Send Queued Msg" button
Memory goes to 11,072k
Respond to message
Memory goes to 11,088k
Click it again
Memory goes to 11,124k
Respond to message
Memory goes to 11,128k

Repeating this process continues to increase memory, although not
consistently. Sometimes it goes up, sometimes it doesn't. And the increase
is not consistent. Once it grabs the memory, though, it doesn't seem to let
it go until the COM+ app is shut down.

If I don't let it sit initially, the first click jumps to 11,776k. The
behavior is pretty much the same.

John

"Mike Dice [MSFT]" <mikedice (AT) online (DOT) microsoft.com> wrote

I modified the test slightly and ran it on my XP Pro, SP1 machine (it has
1.1.4322 version of the CLR on it).

What I did was changes the client so that every time I click the button it
spins in a for loop 10,000 times creating an instance of the component and
calling it's method. I also change the service object to comment out the
MessageBox call (the only thing it's method does).

I see the memory grow to about 14,000k then remain steady at about that
level. At some point (not exactly sure how long since I had to go to a
meeting) that drops back to 860k and sits like that until I push the button
again (thus sending another 10,000) messages in. The drop back is the result
of garbage collection of the instances that were created to service the
requests. Keep in mind that the instances that serviced the requests are
managed, garbage collected objects being called from a non-garbage collected
(COM+) environment. Just because you call IUknown::Release on the wrapper
object that wraps the managed object doesn't mean the managed object goes
away immediately. It is made eligeable for garbage collection when you call
IUnknown::Release on it's wrapper, but that doesn't mean it's immediately
garbage collected. This is why you see memory usage grow with each instance.
What you would expect is that it would continue to grow until the garbage
collector felt it needed to start looking at cleaning things up, at that
point, you'll see some more threads come online (which are doing the work of
cleaning up objects) and you'll see the memory usage reach a steady state.
After some relatively long period of inactivity you'll see the memory usage
drop way back down as the gc does it's work. It is the garbage collector in
the garbage collected environment that makes the decision of when to clean
up the memory.

Hope that helps,
Mike


"Stingray" <nospam> wrote

Mike,

Thanks for the explanation. That makes sense. I figured it had something
to do with GC not being tied to Release. I didn't see the sample giving up
memory but maybe it hasn't taken enough to trigger the GC. Ok, so maybe
this explains the sample's behavior. But it still doesn't explain mine. On
my "real" app, it runs for a while (a few minutes, maybe a few hours,
processing anywhere from 1 to 10,000 messages). Then DLLHOST just suddenly
starts sucking up memory in huge chunks (20M at a time). When it hits 440M
or so, the server grinds to a halt and all activity slows to the point where
the box is unusable. After long click and wait periods I can manage to shut
down the app, the memory is freed and everything is back to normal.
Strange.

John


"Mike Dice [MSFT]" <mikedice (AT) online (DOT) microsoft.com> wrote

Are you calling Marshal.ReleaseComObject(INTERFACE)??


thanks
Anand Rajagopalan
--
This posting is provided "AS IS" with no warranties, and confers no rights.


"Stingray" <nospam> wrote

Hi Anand,
Yes, I'm doing everything "by the book."
John

"Anand Rajagopalan" <anandraj (AT) online (DOT) microsoft.com> wrote