Hard Disk Bottlenecks Performance Counters

Hard Disk Bottlenecks

Physical Disk\Disk Transfers/sec – watch this counter for each physical disk and if it goes above 25 disk I/Os per second then you've got poor response time for your disk

Physical Disk\Idle Time - measures the percent time that your hard disk is idle during the measurement interval, and if you see this counter fall below 20% then you've likely got read/write requests queuing up for your disk which is unable to service these requests in a timely fashion;then is time for a new faster hard disk.

PhysicalDisk\Avg. Read Queue Length Should be less than 2

PhysicalDisk\Avg. Write Queue Length Should be less than 2

PhysicalDisk\ %Disk Time more than 50% indicates a bottleneck

diskperf - is a command line tool that can be used to start disk performance counters from cmd

Note. No counters should be monitored alone you need counters of all groups processor,memory,hard disk,network interface to make a valid decision .Otherwise you might be fulled by the results of only one counter