A bottleneck from a disk can significantly impact response time for applications running on your system.
Physical Disk (instance)\Disk Transfers/sec 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.
By tracking Physical Disk(instance)\% Idle Time, which 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. In this case it's time to upgrade your hardware to use faster disks or scale out your application to better handle the load.
Look for the Physical Disk (instance)\Average Disk Queue length & Physical Disk (instance)\Current Disk Queue length parameters to get more details on the queued up requests.
Friday, February 23, 2007
Disk Bottleneck Symptoms
Subscribe to:
Post Comments (Atom)
1 comment:
Disk bottlenecks can be identified by monitoing Disk Read/Sec and Disk write/sec.Before moitoring these counters we need to make sure that the Disc configuration is made properly.There will be cases where most of the time data will be read from the disk rather writing.In such cases server should be configured in such a way the rate of read % should be high compared to write.It will give a better disk performance if we are setting up the read % to 100 or nearly 100%.The other way if we have more writes to do then do the reverse.If either are improtant need to put the rate at 50:50%.
Post a Comment