SQL Counter: Part 3 (Pages/sec) January 5th, 2008

Vinod Kumar

Memory Object -> Pages/sec
This counter measures the number of memory pages read from or written to disk. Defined as the number of pages read from or written to disk to resolve hard page faults. Hard page faults that 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 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) noncached 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. This is a counter that cannot be measured independently of a system. It is not possible to say that 1000 pages per second is a high or low value; it really depends on the system. The counter is relative to the system and has to be watched to see if things are changing. Make a change and see if the counter goes up or down. In general, adding memory (or allocating more to SQL Server) should lower this counter, but be careful. Understand this counter’s behavior relative to the measured baseline; watch it as changes are made to the system. SQL Server will by default dynamically manage its memory buffer cache, but it is possible to set it manually to a fixed value. If this is done incorrectly too high, then this counter points to the problem.

Tags: , ,

This entry was posted on Saturday, January 5th, 2008 at 14:07 and is filed under Uncategorized. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

Leave a Reply