- Obtaining Maximum Performance While Adding Storage
- Getting the Big Picture
- Detecting Single-Disk Bottlenecks
- Selecting Disk Counters
- Detecting RAID Bottlenecks
- Sizing Additional Disk Capacity for RAID Arrays
- Determining How Many Disks to Add
- Estimating Required Additional RAID Performance Capacity
- Disk Storage Capacity vs. Disk Performance Capacity
- Meeting Your Storage and Performance Needs
Detecting Single-Disk Bottlenecks
Detecting a bottleneck in your disk subsystem is an important first step in helping you determine how much additional disk space and disk performance capacity you need. On NT systems with one hard disk, the disk becomes a bottleneck that throttles the system when the disk can't keep up with the requested workload. As a result, the disk's response time for processing application requests becomes unacceptable. This delay forces applications to wait on disk service.
NT's Performance Monitor is an excellent tool for detecting disk bottlenecks. To collect disk subsystem statistics for use with Performance Monitor, you must type the following at the NT command prompt and reboot the server.
diskperf -ye
Otherwise, the performance counters will all report zero. The -y option tells NT to start the disk counters when you restart NT, and the -e option enables the disk counters that you need to measure the performance of physical disks in striped disk sets. (You might not have a striped disk set now, but turning on these counters will save you from having to reboot later.)