SQL Log : AppDomain unloaded

Our SQL server log is filled with this message:

AppDomain xx (DWH_TOOLKIT.dbo[runtime].xx) created.
AppDomain xx (DWH_TOOLKIT.dbo[runtime].xx) unloaded.
AppDomain xx (DWH_TOOLKIT.dbo[runtime].xx) is marked for unload due to memory pressure.

We are using a CLR procedure to store error messages in a table, file, event log or Microsoft Operations Manager, and i suspect that it is caused by this CLR procedure.

Does anyone have a clue on how to solve this, except for adding more memory, 64Gb should be enough!!

asked Nov 19 '09 at 10:12 AM in Default

Håkan Winther
15k ● 29 ● 35 ● 46

Just found the same problem in the errorlogs of one of our servers.

Jun 30 '10 at 02:53 AM ThomasRushton ♦

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3 answers:

Take a look at a blog post that I wrote, it provides the solution to your exact issue.

SQL Server Memory Configuration: Determining MemToLeave requirements

If you then have further questions then by all means please ask.

answered Nov 19 '09 at 10:19 AM

John Sansom
897 ● 2

Thank you John! You solved my issue in 6 minutes.

Nov 19 '09 at 10:31 AM Håkan Winther

Does it apply to 64 bit version also? I have seen other blog posts that indicates that MemToLeave is no issue in 64 bit.

Nov 19 '09 at 10:51 AM Håkan Winther

So long as you set or rather limit the maximum memory setting of SQL Server to ensure that there is sufficient memory allocated outside of the SQL Server process space, then this should not be an issue for you. Take a look at the following post for an explanation as to why: http://sqlblogcasts.com/blogs/christian/archive/2008/01/07/sql-server-memtoleave-vas-and-64-bit.aspx

Nov 19 '09 at 07:35 PM John Sansom

Good answer, good blog post! Thanks.

Jun 30 '10 at 02:52 AM ThomasRushton ♦

Old blog post link is broken. Here is the new link: http://www.johnsansom.com/sql-server-memory-configuration-determining-memtoleave-settings/

Aug 13 '12 at 06:36 AM eghetto

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Is your issue solved? if not pls let me know, i can help. dbapayal@gmail.com

answered Mar 03 '10 at 05:34 PM

payal
1

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The real question is what problem beyond these entries in the ErrorLog do you have? If you aren't getting failed_virtual_alloc problems, or other execution failures, then you probably shouldn't do anything about this. If your appdomain loads and isn't used often enough, just like everything else in SQL, it will eventually get unloaded. The -g startup parameter can be used to bump the VAS reservation in 32 bit servers, but that only goes so far to prevent the errors being logged. If the AppDomain isn't used frequently enough, it will still unload and you will still get log entries. This isn't a problem on 64 bit SQL Servers because there the VAS limit is 8TB for user mode VAS which is well beyond the physical memory limits currently available. You always have avaiable contiguous VAS on 64 bit servers so there is no VAS reservation or "MemToLeave" area. The engine doesn't even execute that block of code in 64 bit versions.

answered Dec 06 '09 at 01:19 AM