These are the performance parameters that are related to the hardware of the computer system. These include
Commercially, the speed of the CPU is expressed by its cycle time (by length ..e.g.,20 nsec, or by rate ..e.g.,50 MHz.) It is also popularly expressed in MIPS (millions of instructions per second), but since MIPS is totally dependent on the instruction set of the computer, it may not be considered a good standard to compare performance of processors. Owing to this drawback, several standard programs (benchmarks) have been proposed for the purpose of performance comparision. The most popular of them are Whetstone, Dhrystone, Linpack, Perfect Club, SPEC, TPC benchmarks, etc.
The SPEC benchmark consists of CPU intensive programs in C and Fortran, and the results are given as SPECmarks.
All of the disk times have an influence on the overall performance of the system, depending on the nature of the transaction. If the transaction is CPU bound, then the CPU has takes the major role in affecting performance of the system, but if the job is I/O intensive then these disk times play a major role in determining the system's performance metrics.
It is the time that elapses between issuing a request for data, and actually starting the data transfer. In a hard disk, this translates into the time it takes to rotate the disk so that the required sector or cluster is positioned under the read/write head. With a single set of heads, the latency time is on an average one half of the revolution. Latency is just one of many factors that influence disk access speeds.
It is the length of time required to radially move a disk drive's read/write head to a particular location on the disk. The major part of a hard disk's access time is actually seek time.
It is the speed at which a disk drive can transfer information from the drive to the processor, usually measured in megabytes/second. A high data transfer rate speeds up the process and hence improves the system performance.