none
Core leaks most of my RAM? RRS feed

  • General discussion

  • Hello,

    Our company often notices a scenario on Standard 2008 R2 x64 machines where almost all memory is marked "in use" although only a few percent is indicated to be used by applications (and the nature of the running task also supports the theory that there is only low memory usage). However, "Free memory" vanishes and some processes come to a stall (while other still respond fine). No exception on insufficient memory is ever thrown. My programs (if they get the chance to run) never get allocation errors. It seems like the system cripples itself in some of the services. Pagefiles are disabled (they badly interfere with disk caching), the boxes have plenty of RAM to do their jobs. Here's an example situation:

    Resource monitor Memory page displaying about 80 processes with a sum Commit of about 500MB. (The values of other columns are even lower.) Despite this, the summary at the end says: Hardware reserved 2MB, In use 7519MB, Modified 641MB, Standby 28MB, Free 2MB; Available 30MB, Cached 669MB, Total 8190MB.

    The diagrams on the right show: all physical memory used up (almost touching 100%), about 20% commit charge (isn't that supposed to be backed by our 0 byte long pagefiles), and about no hard faults (the ONLY ONE value that is as expected).

    So the smaller problem is (1) that I cannot make sense of these values, the greater is (2) the disappearance of free physical memory and that (3) it does not result in memory allocation errors, but rather hanging processes indefinitely (sometimes even logon fails freezing into waiting for the local session manager).

    Does anyone happen to know a solution/explanation?

    Thanks,
    Levente

     

    PS.: the fun part I forgot: this behavior is noticed mostly when large files are processed. E.g: I just hashed a 250GB file, the app that worked had all memory counters below 10MB. I was unable to quit it (it was stalled by windows while closing). When I ended the process, almost 90% of my RAM became Free (from In use). I think if the app leaked memory, I would have been visible on its memory-counters. I think this might be the same defect of the core that made us disable paging (disk cache filling up free RAM and then forcing application pages again and again to the swapfile) - details in this thread .

    Monday, August 30, 2010 5:19 PM

All replies

  • check with this KB

    http://support.microsoft.com/kb/968675

    maybe it will solve ur problem altho its related to HARDDRIVE slownes

     

    by the way

    1_whats your Storage ? is it SSD?  SAN? ISCSI??

    2_what kind of application you use??

     

     

    Tuesday, October 5, 2010 9:14 AM