# Benchmark

This form allows you to measure the performance of your computer.

There are two tests:

1. Compression with LZMA method
2. Decompression with LZMA method

The benchmark shows a rating in MIPS (million instructions per second). The rating value is calculated from the measured speed, and it is normalized with results of Intel Core 2 CPU with multi-threading option switched off. So if you have modern CPU from Intel or AMD, rating values in single-thread mode must be close to real CPU frequency.

You can change the dictionary size to increase memory usage. Also you can change the number of threads.

The CPU Usage column shows the percentage of time the processor is working. It's normalized for a one-thread load. For example, 180% CPU Usage for 2 threads can mean that average CPU usage is about 90% for each thread.

The Rating / Usage column shows rating normalized for 100% of CPU usage. That column shows performance of the one CPU thread. It must be close to real CPU frequency, if you have modern CPU.

The Total rating shows averages of the compressing and decompression ratings.

Compression speed and rating strongly depend from memory (RAM) latency.

Decompression speed and rating strongly depend on CPU integer operations. For example, an Intel Pentium 4 has big branch misprediction penalty (which is effect of long pipeline) and pretty slow multiply and shift operations. So, the Pentium 4 has pretty low decompressing ratings.

Also the program checks possible errors. If the program shows some error message, in most cases it means that your RAM is defective. If so, don't use 7-Zip for compressing data, since such errors can lead to data losses.