« Previous Next »

Thread: Memory issue - RegionUsageIsVAD

Last post 05-11-2009 4:03 AM by jackiewkc. 6 replies.

Average Rating Rate It (5)

RSS

Page 1 of 1 (7 items)

Sort Posts:

Shortcuts

Search | Active Posts | Unanswered Posts | View all users

  • 04-21-2009, 7:23 AM

    Memory issue - RegionUsageIsVAD

    Reply Contact

    I have a question about an IIS app that I am running. 

    Each instance of that iis app (not workers) chews up 500MB of memory, which is allocated to something called "RegionUsageIsVAD".

    I did some research on this and it seems like 512MB is the default value for RegionUsageIsVAD in .NET version 2.0.50727.1433 (correct me if I am wrong).

    Anyone turning on virtual memory recycling at a level less than 500MB + app normal use causes constant recycling and constant performance issues. Even setting this to the MAX of about 1.4GB (recycle limit) still seems to cause performance issues with the site, even though the event log no longer reports any recycling cycles.

    Can anyone shed some light on this? Is this a general IIS / .NET issue? how can this be fixed? All help would be greatly appreciated.

    Thanks.

    Jackie
    Tags:

  • 04-21-2009, 1:01 PM In reply to

    • anilr
    • Top 10 Contributor
    • Joined on 05-23-2006, 6:13 PM
    • Redmond, WA
    • Posts 2,343

    Re: Memory issue - RegionUsageIsVAD

    Reply Contact

    This is how .Net framework does its memory management - it reserves a contiguous region (and a rather large one on x64 architecture) and then commits stuff as needed - if you are using .Net framework and especially on 64-bit architecture, you would be better off using committed bytes limit for recycling.

    Anil Ruia
    Senior Software Design Engineer
    IIS Core Server

  • 04-21-2009, 1:08 PM In reply to

    Re: Memory issue - RegionUsageIsVAD

    Reply Contact

    Hi Anil,

    Thank you very much for the information. I have a few questions.

    1. Can this value be changed manually? if yes, how?

    2. Would you please provide more details on how to configure recycling in the way you mentioned above?

    3. Is there any website that explain this in more details?

    Thanks again and I really appreciate your help.

    Regards,

    Jackie
    Tags:

  • 04-21-2009, 1:56 PM In reply to

    • anilr
    • Top 10 Contributor
    • Joined on 05-23-2006, 6:13 PM
    • Redmond, WA
    • Posts 2,343

    Re: Memory issue - RegionUsageIsVAD

    Reply Contact

    This seems to be a good blog with details about the CLR GC.  Regarding the IIS recycling setting, use the "private memory usage ..." rather than the "virtual memory usage ..." for your recycling limit.

    Anil Ruia
    Senior Software Design Engineer
    IIS Core Server

  • 04-23-2009, 8:54 AM In reply to

    Re: Memory issue - RegionUsageIsVAD

    Reply Contact

    Thank you very much for the information.

    As this seems to be a problem with the way .net framework manage memory, I was wondering if there is some sort of recommended size of private memory. I know this pretty much depends on the app, but would be great to know if there is any recommendation on this.

    Thanks again for your help.
    Tags:

  • 05-08-2009, 4:44 PM In reply to

    • anilr
    • Top 10 Contributor
    • Joined on 05-23-2006, 6:13 PM
    • Redmond, WA
    • Posts 2,343

    Re: Memory issue - RegionUsageIsVAD

    Reply Contact

    Asking the question at the blog I linked would probably be the fastest way to get an answer.

    Anil Ruia
    Senior Software Design Engineer
    IIS Core Server

  • 05-11-2009, 4:03 AM In reply to

    Re: Memory issue - RegionUsageIsVAD

    Reply Contact

    thanks mate, will do :)
Page 1 of 1 (7 items)
Microsoft Communities