HP Insight Management Agents - Manual (Page 114)

Memory
• Available KBytes —Amount of physical memory available to processes running on the
computer. It is calculated by summing space on the Zeroed, Free, and Stand-by memory
lists. Free memory is ready for use. Zeroed memory is memory filled with zeros to prevent
later processes from seeing data used by a previous process. Standby memory is memory
removed from a working set (its physical memory) of a process in route to a disk, but is still
available to be recalled. This counter displays the last observed value only; it is not an
average.
• Pages/sec—Number of pages read from or written to disk to resolve hard page faults. Hard
page faults occur when a process requires code or data that is not in its working set or
elsewhere in physical memory, and must be retrieved from disk. This counter was designed
as a primary indicator of the faults that cause system-wide delays. It is the sum of Memory:
Pages Input/sec and Memory: Pages Output/sec. It is counted in numbers of pages, so it can
be compared to other counts of pages, such as Memory: Page Faults/sec, without conversion.
It includes pages retrieved to satisfy faults in the file system cache (usually requested by
applications) and in non-cached mapped memory files. This counter displays the difference
between the values observed in the last two samples, divided by the duration of the sample
interval.
• Pages Input/sec—Number of pages read from disk to resolve hard page faults. Hard page
faults occur when a process requires code or data that is not in its working set or elsewhere
in physical memory, and must be retrieved from disk. This counter was designed as a primary
indicator of the faults that cause system-wide delays. It includes pages retrieved to satisfy
faults in the file system cache (usually requested by applications) and in non-cached mapped
memory files. This counter counts numbers of pages, and can be compared to other counts
of pages, such as Memory: Page Faults/sec, without conversion. This counter displays the
difference between the values observed in the last two samples, divided by the duration of
the sample interval.
• Pages Output/sec—Number of pages written to disk to free up space in physical memory.
Pages are written back to disk only if they are changed in physical memory, so they are
likely to hold data, not code. A high rate of pages output might indicate a memory shortage.
Windows NT writes more pages back to disk to free up space when physical memory is in
short supply. This counter counts numbers of pages, and can be compared to other counts
of pages, without conversion. This counter displays the difference between the values
observed in the last two samples, divided by the duration of the sample interval.
• Page Reads/sec—Number of times the disk was read to resolve hard page faults. Hard page
faults occur when a process requires code or data that is not in its working set or elsewhere
in physical memory, and must be retrieved from disk. This counter was designed as a primary
indicator of the kinds of faults that cause system-wide delays. It includes reads to satisfy
faults in the file system cache (usually requested by applications) and in non-cached mapped
memory files. This counter counts numbers of read operations, without regard to the numbers
of pages retrieved by each operation. This counter displays the difference between the
values observed in the last two samples, divided by the duration of the sample interval.
• Page Writes/sec—Number of times pages were written to disk to free up space in physical
memory. Pages are written to disk only if they are changed while in physical memory, so
they are likely to hold data, not code. This counter counts write operations, without regard
to the number of pages written in each operation. This counter displays the difference
between the values observed in the last two samples, divided by the duration of the sample
interval.
• Page Faults/sec—Overall rate at which the faulted pages are handled by the processor. It is
measured in numbers of pages faulted per second. A page fault occurs when a process
requires code or data that is not in its working set (its space in physical memory). This
counter includes both hard faults (those that require disk access) and soft faults (where the
faulted page is found elsewhere in physical memory). Most processors can handle large
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