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Available Bytes Counter
Indicates the amount of physical memory available to processes running on the computer
A consistent value of less than 20–25% of installed RAM is an indication of insufficient memory.
Working Set Counter
If memory is scarce, Process(n)\Working Set tells you how much RAM each process is using.
Pages/sec Counter
Primary indicator to determine whether real memory is a potential bottleneck.
Page Reads/sec counters are hard page faults. A running thread has referenced a page in virtual memory that is not in the process working set. Nor is it a trimmed page marked in transition, but rather is still resident in memory. The thread is delayed for the duration of the I/O operation to fetch the page from disk. The operating system copies the page from disk to an available page in RAM and then redispatches the thread.
Watch out when Pages/sec exceeds 50 per paging disk.
Page Reads/sec Counter
Primary indicator to determine whether real memory is a potential bottleneck.
This counter indicates that the working set of the process is too large for the physical memory and that it is paging to disk. It shows the number of read operations, without regard to the number of pages retrieved in each operation. Higher values indicate a memory bottleneck.
If a low rate of page-read operations coincides with high values for Physical Disk\% Disk Time and Physical Disk\Avg. Disk Queue Length, there could be a disk bottleneck. If an increase in queue length is not accompanied by a decrease in the pages-read rate, a memory shortage exists.
Sustained values of more than five indicate a large number of page faults for read requests.
Pool Nonpaged Bytes Counter
Pages allocated from the Nonpaged pool are always resident in RAM.
Status information about every TCP connection is stored in the Nonpaged pool. Divide by the size of a page to calculate the number of allocated pages.
Watch the value of Memory\Pool Nonpaged Bytes for an increase of 10 percent or more from its value at system startup. If it indeed happens, a significant memory leak is in place.
Paged Pool Bytes Counter
Primarily used to identify processes that are leaking memory.
The number of committed virtual memory pages in the system’s Paged pool. System functions allocate virtual memory pages that are eligible to be paged out from the Paged pool. System functions that are called by processes also allocate virtual memory pages from the Paged pool.
Memory\Paged Pool Bytes reports how much virtual memory is allocated in the system Paged pool.Memory\Paged Pool Resident Bytes is the current number of Paged pool pages that are resident in RAM.The remainder is paged out.
Process(n)\Paged Pool Bytes increase of more than 10% for a specific process may point to leaking memory behavior.
Paged Pool Failures Counter
Server\Paged Pool Failures Counter:
Primarily used to identify a virtual memory shortage in the Paged pool.
The file Server service has a number of functions that allocate virtual memory pages from the Paged pool. If a memory leak exhausts the Paged pool, the file Server service might encounter difficulty in allocating virtual memory from the Paged pool. If a call to allocate virtual memory fails, the file Server service recovers gracefully from these failures and reports on them. Because many other applications and system functions do not recover gracefully from virtual memory allocation failures, this counter can be the only reliable indicator that a memory leak caused these allocation failures.
Any nonzero value of this counter indicates a bottleneck.
Committed Bytes Counter
The Committed Bytes:RAM ratio is a secondary indicator of a real memory shortage.
When Committed Bytes:RAM ratio exceeds 1.5, it clearly indicates real memory bottleneck. |
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