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The statistics feature of Storage Foundation for Windows provides I/O statistics to let you do performance tuning to improve overall disk and system performance.
Storage Foundation for Windows provides the following statistics parameters:
Read Requests/Second
The number of read requests per second for selected storage objects.
Write Requests/Second
The number of write requests per second for selected storage objects.
Read Blocks/Second
The amount of read request data (in blocks per second) that is processed for selected storage objects. It is the throughput on the read requests made.
Write Blocks/Second
The amount of write request data (in blocks per second) that is processed for selected storage objects. It is the throughput on the write requests made.
Average Time/Read Block
The average time in microseconds that it takes to process a read block from the time a request is made until the data is returned.
Average Time/Write Block
The average time in microseconds that it takes to process a write block from the time a request is made until the data is returned.
Read and Write Requests/Second
The number of read and write requests per second for selected storage objects.
Read and Write Blocks/Second
The number of read and write blocks per second for selected storage objects.
Queue Depth
The current number of read and write requests in the queue for selected disks. It does not apply to volumes and subdisks.
With these statistical tools, you can improve disk and system performance by the following actions:
Identifying high I/O areas that are known as "hot spots."
Moving data among physical drives to evenly balance the I/O load among the disk drives. This is known as "load balancing."
Bottlenecks occur when a program or device uses too much disk I/O, creating a hot spot and degrading performance. By monitoring a system's I/O, you can find the problem areas and prevent bottlenecks, thus ensuring smooth operation. The Performance Monitoring utility of Storage Foundation for Windows (SFW) lets you continuously monitor and tune system performance. You can make adjustments by moving subdisks from an area of high I/O usage to another disk that has lower usage. You also have the feature of splitting subdisks and joining them back together again. This gives you added flexibility of breaking subdisks down to smaller parts and then moving them.
You can view the statistics in a real-time format in the Online Monitoring window. You can also set up the statistics collection so that you can do an analysis of the statistics over time with the historical statistics collection and graphing functions.
The table below summarizes the similarities and differences between the two types of statistics.
Table: Comparison of real-time and historical statistics
For details on these two types of statistics formats, see the following topics: