What is the CPU Throughput? ie instructions per second (IPS|TIPS|GIPS|MIPS)

About

The throughput metrics in a CPU context is the number of instructions that can be executed in a unit of time at a given clock rate.

The performance or speed of a processor depends on e.g.:

• the clock rate
• and the instructions per clock (IPC),

which together are the factors for the instructions per second (IPS) that the CPU can perform.

Maximum Throughput Calculation

The maximum Throughput is the amount of data that the CPU is able to process without any latency by interfering processes.

To calculate the Maximum Throughput in bytes we use the following equation:

<MATH>T = \frac{W}{8} * (S*1,000,000)</MATH>

Where:

• T equals maximum throughput,
• W equals bus width
• and S equals bus speed in MHz.

A 33MHz CPU operating on a 32 bits wide bus would be then able to process more than:

• 1.32E+8 Bytes per second (ie 132 * 1,000,000)
• of 125.8 megabytes per second. (ie 132 * 1,000,000 / 1024 / 1024)

The equation above might be accurate to a certain extent but in reality the number might drop a bit caused by overhead.

¹⁾) ²⁾