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Is Windows System Cache causing a problem? RRS feed

  • Question

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    I wrote a service that copies huge files (400 MB and greater) from a file server using the WIN32 file copy function. 

     

    I have another service that is doing very complex transaction processing and is set to "above normal" process priority.  Each transaction takes about 8 seconds unless a large file copy occurs.

     

    When the first service copies smaller files (less than 250 MB), I don't see any impact to what the second service is doing.  When larger files are copied, the second service takes 16 seconds or more per transaction.  CPU% for first service stays around 8% while CPU% for second service drops from 99% on a transaction down to about 45%.  Memory consumption stays level.

     

    The second service is not performing any known disk i/o.  It does use shared read-only memory map files.

     

    Is Windows System Cache being used by both the WIN32 file copy and by the map mem file?  Is it possible that map mem files are loaded into the Windows System cache and are being wiped out when a large copy occurs?

     

    Thanks, Mark

    Friday, April 13, 2007 10:05 PM