JSI Tip 1042. High Pages/Sec may not be due to paging.


When monitoring Memory - Pages/Sec, high values may be the result of an application performing sequential reads on a memory mapped file.

Performance Monitor defines the Memory Pages/sec counter as:


   Pages/sec is the number of pages read from the disk or written to the disk to
   resolve memory references to pages that were not in memory at the time of the
   reference. This is the sum of Pages Input/sec and Pages Output/sec. This
   counter includes paging traffic on behalf of the system Cache to access file
   data for applications. This is the primary counter to observe if you are
   concerned about excessive memory pressure (that is, thrashing), and the
   excessive paging that may result. This counter, however, also accounts for
   such activity as the sequential reading of memory mapped files, whether
   cached or not. The typical indication of this is when you see high number of
   Memory: Pages/sec, a "normal" (average, relative to the system being
   monitored) or high number of Memory: Available Bytes, and a normal or small
   amount of Paging File: % Usage. In the case of a non-cached memory mapped
   file, you also see normal or low cache (cache fault) activity.
You should monitor additional counters to get a better picture of memory pressure.
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