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Windows Performance

Using Perfmon

  • See realtime info for a data collector set: It has to have been stopped at least once, then open the generated report, hit 'view current activity Ctrl-T'

Disk Performance

What perfmon counters can I trust when using SAN disks? | Troubleshooting SQL Server Storage Problems

What are the things to be measured?

  • Latency
    • How fast the disk responds. If it's under load, latency will increase
  • Queue length
    • High number means the disk isn't keeping up with requests
  • Throughput
    • Sustained transfer, ie large file copy
  • IOPS
    • Because throughput isn't everything
Common term Perfmon Counter name
Average IO Size Avg. Disk Bytes / Transfer
Average Latency Avg. Disk sec / Transfer
Throughput Disk Bytes / sec
IOPS Disk Transfers / sec

Latency is normally expressed in milliseconds (ms), but Perfmon does display the value in seconds, for example 0.015 seconds = 15 ms.

Throughput is often expressed in MB/sec, but Perfmon in Windows 2003 displays this in Bytes/second, e.g. 382,090,819 meaning 382 MB/s.

Windows Performance Monitor and Disk usage – Rickard Nobel

Collector Sets

Data Manager

Change from Delete Largest First, to Delete Oldest First

Scheduled Task

They are already set up, but not enabled, in Windows/PLA


Trigger: Daily at 12:00AM
Trigger: At startup (Delay for 15 minutes)
Settings: If the task is already running, Stop the existing instance

Remote Desktop Servers in Hyper-V

Watching performance to see if there's a spike of VM activity at a certain time:

  • Hyper-V Hypervisor Virtual Processor > % Guest Run Time > All Instances
  • PhysicalDisk > Avg Disk sec/Read + Avg Disk sec/Write > Total
windows_performance.txt · Last modified: 2018/04/09 09:56 (external edit)