Memory – HP ProLiant DL380 G5 Server User Manual

Page 34

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Context Block Queue/sec—Rate per second at which the work context blocks must be placed on the FSP queue

of the server to await server action.

% Total PageFile Usage (Thresholds Supported) —Amount in percent of the Page File instance in use. For details,

see the Process Object: Page File Bytes information.

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 dis). 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 numbers of soft faults without consequence. However, hard faults can cause significant delays. This

counter displays the difference between the values observed in the last two samples, divided by the duration of

the sample interval.

Cache Bytes—Sum of the System Cache Resident Bytes, System Driver Resident Bytes, System Code Resident

Bytes, and Pool Paged Resident Bytes counters. This counter displays the last observed value only; it is not an

average.

Cache Faults/sec—Number of faults, that occur when a page sought in the file system cache is not found and

must be retrieved from elsewhere in memory (a soft fault) or from disk (a hard fault). The file system cache is an

area of physical memory that stores recently used pages of data for applications. Cache activity is a reliable

indicator of most application I/O operations. This counter counts the number of faults, without regard for the

number of pages faulted in each operation.

Pool Nonpaged Bytes—Number of bytes in the nonpaged pool, an area of system memory (physical memory

used by the operating system) for objects that cannot be written to disk, but must remain in physical memory as

long as they are allocated. Memory: Pool Nonpaged Bytes is calculated differently than Process: Pool

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