dllhost.exe...... the work of the devil?
-
Here I go again
We use COM+ object to access one of our dbs, a technology which I know nada about but which our developers have implemented anyway. Well the dllhost.exe which runs the COM+ objects keeps eating memory through the day and SQL Server eats (to keep up, I presume). If I don't restart the object by logging off and back on every morning my SQL server will grind to a halt.
I found an article relating to NT which sounds similar (Q229739) but I'm not quite following it. Can anyone enlighten me as to what may be happening and what I might do(apart from shooting the developers in question...I've thought of that one)
Sorry to be a pest,
David
-
COM+ in theory isnt that big a deal, its just a standard COM component (which is really just some VB or whatever code in a class or classes, nothing bug). COM+ gives you built in transactions, lets you run the component using role based security, do some other interesting but not useful to me yet kinda things.
I dont use it much, so you may be better off trying a VB (or whatever language) group to ask. Im sure you've thought of this - the key is to figure out why it keeps growing - one reason might be that resources (object references) are never getting cleaned up properly. I'd suggest getting your developers to add some logging so you can see what is happening, especially for error trapping.
Post anytime - we enjoy the questions and we all learn from them!
Andy
-
Thanks Andy,
I was a bit scardy of going to a VB site first.... that's still very much alchemy to me(or Quackery, the jury's out). I'll take a snoop around their haunts and see what I can find.
David
-
Is SQL Server grinding to a halt or the server itself (OS, et. al,). If it's just the SQL Server, a temporary solution until you find out why Component Services is eating up memory and not giving back is to statically allocate memory for SQL Server to ensure it doesn't get taken down.
Still though, Andy's right, in that the developers are really going to have to lend a hand to determine why the Component Services components keep chewing up memory.
K. Brian Kelley
http://qa.sqlservercentral.com/columnists/bkelley/
K. Brian Kelley
@kbriankelley -
That's a good plan ....but...
As it is I have an acceptable workaround of logging off and logging back in in the mornings and I amn't confident enough with SQL server to go dickeying around with the memory allocation.
-
You shouldnt have to change any memory settings. The COM+ thing doesnt need to (and you probably dont want) run on the SQL box itself. Doesnt mean you wont still have some kind of resource leak, but might help. You might help things along by looking to see if the object is holding a lot of connections open, running bad queries, etc.
Andy
-
Hi
SP2 of Win2k resolved this issue for us. The DLLHOST.exe chewed around 30Mb then stopped there and cached nicely.
Cheers
Chris
Chris Kempster
www.chriskempster.com
Author of "SQL Server Backup, Recovery & Troubleshooting"
Author of "SQL Server 2k for the Oracle DBA" -
Ooooo. That's handy. Do you know what the actual bug that SP2 fixed for you was? Q265379? It would be nice to be able to go to the devs with suggestions rather than just say "Ug!! Component broke, you fix"
I've definitely been able to nail it down to COM+ this morning but I haven't check in with any of the VB sites just yet.
Somewhat premature I know, but thanks for you help thus far it's been really beneficial.
David
-
So you have a problem with premature congratulations?
Glad we could help!
Andy
-
AAAAAAAAAAAAAH
-
Let us know what happens. Haven't worked too much with COM+, but we used COM to connect to SQL and never had to worry about restarts or memory leaks.
Let us know.
Steve Jones
Follow me on Twitter: http://www.twitter.com/way0utwest
Forum Etiquette: How to post data/code on a forum to get the best help
My Blog: www.voiceofthedba.com -
Wilco
-
Dragging this thread back up. Just thought I'd let you know, I haven't applied SP2 (business reasons and fear of Clustering...ooooooooh!) but I did some more research and the post SP2 hotfix includes a fix for memory leak caused by COM+. It looks good. We're coming to the end of a big business project this week so once it's done I should be given the go ahead to service pack.
Watch this space.
DeltaKilo
-
What is the hotfix? We run applications here that are highly reliant on COM+ and I'd be interested in reading up on what the fix is.
K. Brian Kelley
http://qa.sqlservercentral.com/columnists/bkelley/
K. Brian Kelley
@kbriankelley -
http://support.microsoft.com/default.aspx?scid=kb;en-us;Q293646
And you should see the leak. If we don't kill the dllhost.exe in the morning before production it will gooble up memory (5-600MB of 1GB by early aftenoon). Quite spectacular really
DeltaKilo
Viewing 15 posts - 1 through 15 (of 17 total)
You must be logged in to reply to this topic. Login to reply