System Counters

System Counters

Guidelines for Monitoring System Counters for Sitecore Servers

  • Sitecore servers should be periodically tuned for performance
  • Use the Performance Monitor tool to review the following system performance counters

Steps for Monitoring Performance Counters using a Template

  • Run the Performance Monitor application
  • Right-click 'Performance > Data Collector Sets > User Defined' and select 'New > Data Collector Set'
  • Type 'System' and click 'Create from a template(RSysteecommended)'
  • Select the 'System Performance' template and click Next
  • Accept the default file system path %systemdrive%\PerfLogs\Admin\Sitecore and click Next
  • Select 'Start this data collector set now' and click Finish
  • Set the Properties of Data Collector Sets > User Defined > System Performance
    • Uncheck 'Overall Duration' on the 'Stop Condition' tab
  • Set the Properties of Data Collector Sets > User Defined > System Performance > Performance Counter
    • Set the interval to 15 minutes

Memory Object Critical Counters

  • Available Bytes displays the amount of physical memory immediately available for system use or for allocation to a process
    • Preferred is 10% of physical memory
  • Committed Bytes displays the amount of physical memory that has space reserved on the disk paging file
    • Preferred is less than 75 percent of physical memory
  • Pages/sec displays the rate at which pages are read from or written to disk to resolve hard page faults
    • Preferred range is 0 to 20
    • Investigate if over 80
  • Pool Nonpaged Bytes displays the amount of physical memory used by the operating system for objects that must remain in physical memory when they are being used
    • A flat horizontal line indicates a steady value
    • A slow rise could indicate a memory leak
  • Pool Paged Bytes displays the amount of physical memory used by the operating system for objects that can be written to disk when they are not being used

Network Interface Object Critical Counters

  • Bytes Total/sec displays the rate at which bytes are sent and received over each network adapter, including framing characters
  • Output Queue Length displays the length of the output packet queue (in packets)
    • Network delays and bottlenecks are likely when the value is higher than two, especially when the Network Utilization is greater than 25%

Paging File Object Critical Counters

  • % Usage is the amount of the Page File instance in use in percent form
  • % Usage Peak  is the peak usage of the Page File instance in percent

Physical Disk Object Critical Counters

  • % Disk Time displays the percentage of elapsed time that the disk drive was busy servicing read or write requests
    • Preferred value is less than 50 percent
  • Avg. Disk Queue Length is the average number of both read and write requests that were queued for the selected disk during the sample interval
    • Disk delays and bottlenecks are likely when the value is greater than two, especially when the % Disk Time is greater than 50 percent

Process Object Critical Counters for w3wp.exe (Worker Process for Sitecore)

  • Private Bytes displays the amount of memory used by this process that cannot be shared with other processes
  • Virtual Bytes displays the amount of the virtual address space the process is using
  • Page File Bytes displays the amount of virtual memory that this process has reserved in the paging file
  • IO Data Operations/sec displays the rate at which the process is issuing read and write Input/Output (I/O) operations
    • File I/O
    • Network I/O
    • Device I/O
  • IO Other Operations/sec displays the rate at which the process is issuing control functions and other I/O operations that are neither read nor write operations
  • % Processor Time displays the percentage of time that the process threads used the processor to execute instructions

Processor Object Critical Counters

  • % Processor Time displays the percentage of time that the processor spent executing a non-Idle thread
    • Preferred value is less than 75 percent
    • A high value with Processor Queue Length greater than four could indicate a processor bottleneck

System Object Critical Counters

  • Context Switches/sec measures the rate at which processors are switched from one thread to another
    • A running thread voluntarily relinquishes the processor
    • A running thread is preempted by a higher priority ready thread
    • The processor switches between user-mode and privileged (kernel) mode
    • A high number indicates high contention in locks or many switches between user and kernel modes
  • Processor Queue Length is the number of threads in the processor queue
    • This counter shows ready threads only, not threads that are running
    • There is a single queue for processor time so divide this value by the number of processors
    • A sustained processor queue of less than 10 threads per processor is normally acceptable

Sources