Failed to map 8388608 bytes of contiguous memory

  • My customer is running a small e-commerce site on a SQL Server 2008 R2 SP2 Workgroup Edition x64. The SQL Server runs on a Windows Server 2008 R2 Standard x64 SP1 having 12GB RAM. I've allocated a max memory of 5GB to SQL (the min memory is o) and the account used by the SQL Server service has been granted the "Lock pages in memory" right. The database and the site (.NET 2.0 ) are situated on the same machine. The machine has 2 NUMA nodes. I've set the processor affinity to one node for SQL and to the other node for IIS.

    Apart from CPU spikes due to a piece of sloppy programming, there seems to be no other area where things are going wrong.

    However, this message appears every few days in the SQL error log : "Failed to map 8388608 bytes of contiguous memory". I've found no related error message in the Windows or application logs.

    Where should I begin investigating in order to find the cause of this error?

    Thank you...

  • This was for v2000/2005 - don't know if it still applies

    http://support.microsoft.com/kb/903002


    Cursors never.
    DTS - only when needed and never to control.

  • dmoldovan (12/11/2012)


    My customer is running a small e-commerce site on a SQL Server 2008 R2 SP2 Workgroup Edition x64. The SQL Server runs on a Windows Server 2008 R2 Standard x64 SP1 having 12GB RAM. I've allocated a max memory of 5GB to SQL (the min memory is o) and the account used by the SQL Server service has been granted the "Lock pages in memory" right. The database and the site (.NET 2.0 ) are situated on the same machine. The machine has 2 NUMA nodes. I've set the processor affinity to one node for SQL and to the other node for IIS.

    Apart from CPU spikes due to a piece of sloppy programming, there seems to be no other area where things are going wrong.

    However, this message appears every few days in the SQL error log : "Failed to map 8388608 bytes of contiguous memory". I've found no related error message in the Windows or application logs.

    Where should I begin investigating in order to find the cause of this error?

    Thank you...

    Usually this is something seen on 32 bit machines and MemToLeave, but you state you are on x64 which usually doesn't have a problem there. But you do have a VERY low max memory set too. I note however that only about twice in 15 years of consulting have I seen valid reasons for messing with processor affinity and something could be screwy with that (and the fact that you have NUMA hardware too).

    Are you getting any other errors? Please post the ENTIRE error message. Is this repeatable at/near the same time of day or random? Is this a virtual machine by any chance?

    I would watch memory usage of all items on the box and see if you can't increase that max mem setting for SQL Server. You may also want to set up a profiler trace to local disk with rollover files to capture activity during the event. Be sure to delete the files as they stack up to avoid filling up a drive (and do NOT do STMT COMPLETED!!!).

    Do you use a lot of XPs, CLR, Full Text, etc?

    You may want to consider getting a professional on board for a few hours to give your system a quick review. Lots of potential issues here and it could take you days or weeks of hunt-and-peck forum stuff and still not isolate a cause.

    Best,
    Kevin G. Boles
    SQL Server Consultant
    SQL MVP 2007-2012
    TheSQLGuru on googles mail service

  • Has there been a definitive resolution to this? I just started getting the same error message. The SQL box is a VM with 8gb memory SS2K8R2 Enterprise SP2 64 bit.

    Kurt

    Kurt W. Zimmerman
    SR DBA
    Lefrak Organization
    New York, NY

    http://www.linkedin.com/in/kurtwzimmerman

  • Are you using the trace flag to enable large pages?

    Gail Shaw
    Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
    SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

    We walk in the dark places no others will enter
    We stand on the bridge and no one may pass
  • No.

    Here is the start up:

    -dC:\Program Files\Microsoft SQL Server\MSSQL10_50.MSSQLSERVER\MSSQL\DATA\master.mdf;

    -eC:\Program Files\Microsoft SQL Server\MSSQL10_50.MSSQLSERVER\MSSQL\Log\ERRORLOG;

    -lC:\Program Files\Microsoft SQL Server\MSSQL10_50.MSSQLSERVER\MSSQL\DATA\mastlog.ldf

    Kurt W. Zimmerman
    SR DBA
    Lefrak Organization
    New York, NY

    http://www.linkedin.com/in/kurtwzimmerman

  • Greetings all;

    Just an update. I was experiencing issues with the entire application stack so I was able to take advantage of rebooting the SQL Server. It appears to have resolve the "Failed to map 8388608 bytes of contiguous memory" issue.

    Kurt

    Kurt W. Zimmerman
    SR DBA
    Lefrak Organization
    New York, NY

    http://www.linkedin.com/in/kurtwzimmerman

  • I am not sure. But could it be a virtual memory related error? Due to disk fragmentation, large memory area for page file can not be allocated!!!!!

  • I'm not sure exactly what the actual cause of the problem was. I presumed that it had to do with the way the VM environment allocated memory.

    In the future if I need to make any changes to the maximum server memory I will insure I do it during a maintenance window where I can restart the server.

    Thanks for your response.

    Kurt

    Kurt W. Zimmerman
    SR DBA
    Lefrak Organization
    New York, NY

    http://www.linkedin.com/in/kurtwzimmerman

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