By opting for the Windows 7 Certificate: Server Administrator certificate
PhysicalDisk > % Disk Time and LogicalDisk > % Disk Time Shows the amount of time the disk is busy because it is servicing read or write requests. If the disk is busy more than 90% of the time, you will improve performance by adding another disk channel and splitting the disk I/O requests between the channels.
PhysicalDisk > Current Disk Queue Length and LogicalDisk > Current mcitp enterprise administrator Disk Queue Length Indicates the number of outstanding disk requests that are waiting to be processed. On aver- age, this value should be less than 2.
LogicalDisk > % Free Space Specifies how much free disk space is available. This counter should be at least 15%.
When you suspect that you have a disk subsystem bottleneck, the first thing you should check is your memory subsystem. Insufficient physical memory can cause excessive paging, which in turn affects the disk subsystem. If you do not have a memory problem, you can try the fol- lowing solutions to improve disk performance:
Confirm that you have the latest drivers for your disk host adapters. Use disk striping to take advantage of multiple I/O channels. Balance heavily used files on multiple I/O channels. Add another disk controller for load balancing.
Use Disk Defragmenter to consolidate files so that disk space and data access are optimized. If you are on a network, distribute applications that have high disk I/O through the Distributed File System (DFS) to balance workload.
In Windows NT 4, you enabled all disk counters through the Diskperf –y command. Physical and logical disk counters are automatically enabled in Windows Vista. In Exercise 11.3, you will monitor your disk subsystem. This exercise assumes that you have completed the previous exercises in this chapter.
In the Performance Monitor window, click the Add button on the toolbar. In the Add Counters mcitp server administrator dialog box, specify the following performance objects and counters: Select PhysicalDisk from the Performance Object drop-down list, select % Disk Time from the counter list box, select _Total in the Instances list box, and click Add.
Select PhysicalDisk from the Performance Object drop-down list, select Current Disk Queue Length from the counter list box, select _Total in the Instances list box, and click Add.
Select LogicalDisk from the Performance Object drop-down list, select % Idle Time from the counter list box, select _Total in the Instances list box, and click Add.
Processing your request, Please wait....
