Memory Object

Object: Memory Index:004 Novice

The Memory object type includes those counters that describe the behavior of both real and virtual memory on the computer. Real memory is allocated in units of pages. Virtual memory may exceed real memory in size, causing page traffic as virtual pages are moved between disk and real memory.

Available Bytes Expert

Available Bytes displays the size of the virtual memory currently on the Zeroed, Free, and Standby lists. Zeroed and Free memory is ready for use, with Zeroed memory cleared to zeros. Standby memory is memory removed from a process's Working Set but still available. Notice that this is an instantaneous count, not an average over the time interval.

Index: 024 Default Scale: 0.00001

Counter Type: PERF_COUNTER_RAWCOUNT Counter Size: 4 bytes

Cache Bytes Advanced

Cache Bytes measures the number of bytes currently in use by the system Cache. The system Cache is used to buffer data retrieved from disk or LAN. The system Cache uses memory not in use by active processes in the computer.

Index: 818 Default Scale: 0.00001

Counter Type: PERF_COUNTER_RAWCOUNT Counter Size: 4 bytes

Cache Bytes Peak Advanced

Cache Bytes Peak measures the maximum number of bytes used by the system Cache. The system Cache is used to buffer data retrieved from disk or LAN. The system Cache uses memory not in use by active processes in the computer.

Index: 820 Default Scale: 0.00001

Counter Type: PERF_COUNTER_RAWCOUNT Counter Size: 4 bytes

Cache Faults/sec Wizard

Cache Faults occur whenever the Cache manager does not find a file's page in the immediate Cache and must ask the memory manager to locate the page elsewhere in memory or on the disk so that it can be loaded into the immediate Cache.

Index: 036 Default Scale: 0.1

Counter Type: PERF_COUNTER_COUNTER Counter Size: 4 bytes

Commit Limit Wizard

Commit Limit is the size (in bytes) of virtual memory that can be committed without having to extend the paging file(s). If the paging file(s) can be extended, this is a soft limit.

Index: 030 Default Scale: 0.000001

Counter Type: PERF_COUNTER_RAWCOUNT Counter Size: 4 bytes

Committed Bytes Expert

Committed Bytes displays the size of virtual memory (in bytes) that has been Committed (as opposed to simply reserved). Committed memory must have backing (that is, disk) storage available, or must be assured never to need disk storage (because main memory is large enough to hold it). Notice that this is an instantaneous count, not an average over the time interval.

Index: 026 Default Scale: 0.000001

Counter Type: PERF_COUNTER_RAWCOUNT Counter Size: 4 bytes

Demand Zero Faults/sec Wizard

Demand Zero Faults are the number of page faults for pages that must be filled with zeros before the fault is satisfied. If the Zeroed list is not empty, the fault can be resolved by removing a page from the Zeroed list.

Index: 038 Default Scale: 0.1

Counter Type: PERF_COUNTER_COUNTER Counter Size: 4 bytes

Free System Page Table Entries Wizard

The number of Page Table Entries not currently in use by the system.

Index: 678 Default Scale: 0.01

Counter Type: PERF_COUNTER_RAWCOUNT Counter Size: 4 bytes

Page Faults/sec Novice

Page Faults/sec is a count of the Page Faults in the processor. A page fault occurs when a process refers to a virtual memory page that is not in its Working Set in main memory. A Page Fault will not cause the page to be fetched from disk if that page is on the standby list, and hence already in main memory, or if it is in use by another process with whom the page is shared.

Index: 028 Default Scale: 0.1

Counter Type: PERF_COUNTER_COUNTER Counter Size: 4 bytes

Page Reads/sec Expert

Page Reads/sec is the number of times the disk was read to retrieve pages of virtual memory necessary to resolve page faults. Multiple pages can be read during a disk read operation.

Index: 042 Default Scale: 1

Counter Type: PERF_COUNTER_COUNTER Counter Size: 4 bytes

Page Writes/sec Expert

Page Writes/sec is a count of the number of times pages have been written to the disk because they were changed since last retrieved. Each such write operation may transfer a number of pages.

Index: 050 Default Scale: 1

Counter Type: PERF_COUNTER_COUNTER Counter Size: 4 bytes

Pages Input/sec Novice

Pages Input/sec is the number of pages read from the disk to resolve memory references to pages that were not in memory at the time of the reference. This counter includes paging traffic on behalf of the system Cache to access file data for applications. This is an important counter to observe if you are concerned about excessive memory pressure (that is, thrashing), and the excessive paging that may result.

Index: 822 Default Scale: 1

Counter Type: PERF_COUNTER_COUNTER Counter Size: 4 bytes

Pages Output/sec Advanced

Pages Output/sec is a count of the number of pages that are written to disk because the pages have been modified in main memory.

Index: 048 Default Scale: 1

Counter Type: PERF_COUNTER_COUNTER Counter Size: 4 bytes

Pages/sec Novice

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.

Index: 040 Default Scale: 1

Counter Type: PERF_COUNTER_COUNTER Counter Size: 4 bytes

Pool Nonpaged Allocs Wizard

Pool Nonpaged Allocs is the number of calls to allocate space in the system Nonpaged Pool. Nonpaged Pool is a system memory area where space is acquired by operating system components as they accomplish their appointed tasks. Nonpaged Pool pages cannot be paged out to the paging file, but instead remain in main memory as long as they are allocated.

Index: 064 Default Scale: 0.01

Counter Type: PERF_COUNTER_RAWCOUNT Counter Size: 4 bytes

Pool Nonpaged Bytes Advanced

Pool Nonpaged Bytes is the number of bytes in the Nonpaged Pool, a system memory area where space is acquired by operating system components as they accomplish their appointed tasks. Nonpaged Pool pages cannot be paged out to the paging file, but instead remain in main memory as long as they are allocated.

Index: 058 Default Scale: 0.00001

Counter Type: PERF_COUNTER_RAWCOUNT Counter Size: 4 bytes

Pool Paged Allocs Wizard

Pool Paged Allocs is the number of calls to allocate space in the system Paged Pool. Paged Pool is a system memory area where space is acquired by operating system components as they accomplish their appointed tasks. Paged Pool pages can be paged out to the paging file when not accessed by the system for sustained periods of time.

Index: 060 Default Scale: 0.01

Counter Type: PERF_COUNTER_RAWCOUNT Counter Size: 4 bytes

Pool Paged Bytes Advanced

Pool Paged Bytes is the number of bytes in the Paged Pool, a system memory area where space is acquired by operating system components as they accomplish their appointed tasks. Paged Pool pages can be paged out to the paging file when not accessed by the system for sustained periods of time.

Index: 056 Default Scale: 0.00001

Counter Type: PERF_COUNTER_RAWCOUNT Counter Size: 4 bytes

Pool Paged Resident Bytes Advanced

Pool Paged Resident Bytes is the size of paged Pool resident in core memory. This is the actual cost of the paged Pool allocation, since this is actively in use and using real physical memory.

Index: 066 Default Scale: 0.00001

Counter Type: PERF_COUNTER_RAWCOUNT Counter Size: 4 bytes

System Cache Resident Bytes Advanced

System Cache Resident Bytes is the number of bytes currently resident in the global disk cache.

Index: 076 Default Scale: 0.00001

Counter Type: PERF_COUNTER_RAWCOUNT Counter Size: 4 bytes

System Code Resident Bytes Advanced

System Code Resident Bytes is the number of bytes of System Code Total Bytes currently resident in core memory. This is the code working set of the pagable executive. In addition to this, there is another ~300k bytes of non-paged kernel code.

Index: 070 Default Scale: 0.00001

Counter Type: PERF_COUNTER_RAWCOUNT Counter Size: 4 bytes

System Code Total Bytes Advanced

System Code Total Bytes is the number of bytes of pagable pages in ntoskrnl.exe, hal.dll, and the boot drivers and file systems loaded by ntldr/osloader.

Index: 068 Default Scale: 0.00001

Counter Type: PERF_COUNTER_RAWCOUNT Counter Size: 4 bytes

System Driver Resident Bytes Advanced

System Driver Resident Bytes is the number of bytes of System Driver Total Bytes currently resident in core memory. This number is the code working set of the pagable drivers. In addition to this, there is another ~700k bytes of non-paged driver code.

Index: 074 Default Scale: 0.00001

Counter Type: PERF_COUNTER_RAWCOUNT Counter Size: 4 bytes

System Driver Total Bytes Advanced

System Driver Total Bytes is the number of bytes of pagable pages in all other loaded device drivers.

Index: 072 Default Scale: 0.00001

Counter Type: PERF_COUNTER_RAWCOUNT Counter Size: 4 bytes

Transition Faults/sec Wizard

Transition Faults/sec is the number of page faults resolved by recovering pages that were in transition, that is, being written to disk at the time of the page fault. The pages were recovered without additional disk activity.

Index: 034 Default Scale: 0.1

Counter Type: PERF_COUNTER_COUNTER Counter Size: 4 bytes

Write Copies/sec Wizard

Write Copies/sec is the number of page faults that have been satisfied by making a copy of a page when an attempt to write to the page is made. This is an economical way of sharing data since the copy of the page is only made on an attempt to write to the page; otherwise, the page is shared.

Index: 032 Default Scale: 1

Counter Type: PERF_COUNTER_COUNTER Counter Size: 4 bytes