Some important server perfmon counters to monitor

http://www.enduria.eu/key-performance-counters-and-their-thresholds-for-windows-server-recommended-by-microsoft/

Some of the more important ones include:

Processor:

Processor\% Processor Time (This counter is the primary indicator of processor activity. High values many not necessarily be bad. However, if the other processor-related counters are increasing linearly such as % Privileged Time or Processor Queue Length, high CPU utilization may be worth investigating)

• Less than 60% consumed = Healthy
• 51% – 90% consumed = Monitor or Caution
• 91% – 100% consumed = Critical or Out of Spec

\Memory\Available MBytes

(Available MBytes is the amount of physical memory available to processes running on the computer, in Megabytes, rather than bytes as reported in Memory\Available Bytes. The Virtual Memory Manager continually adjusts the space used in physical memory and on disk to maintain a minimum number of available bytes for the operating system and processes. When available bytes are plentiful, the Virtual Memory Manager lets the working sets of processes grow, or keeps them stable by removing an old page for each new page added. When available bytes are few, the Virtual Memory Manager must trim the working sets of processes to maintain the minimum required)

• Low on available memory – less than 10% available
• Very low on available memory – less than 5% available
• Decreasing trend of 10MB’s per hour. This could indicate a memory leak.

\Memory\Pages/sec

(If it is high, then the system is likely running out of memory by trying to page the memory to the disk. Pages/sec is the rate at which pages are read from or written to disk to resolve hard page faults. This counter is 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) non-cached mapped memory files)

• High pages/sec – greater than 1000 (If it’s higher than 1000, the system is could be beginning to run out of memory. Consider reviewing the processes to see which processes are taking up the most memory or consider adding more memory)
• Very high average pages/sec – greater than 2500 (If this is greater than 2500, the system could be experiencing system-wide delays due to insufficient memory. Consider reviewing the processes to see which processes are taking up the most memory or consider adding more memory)
• Critically high average pages/sec – greater than 5000 (If this is greater than 5000. If so, the system is most likely experiencing delays due to insufficient memory.