Storage system

A data compression system, comprising:

• a compression unit that is capable of compressing data by a first compression method and a second compression method;
• a determination unit that determines whether a compression rate of the data compressed by the first compression method is better than a predetermined reference;
• and
• an output unit that outputs the data compressed by the compression unit, wherein
• the output unit outputs data obtained by compressing the data with the compression method having a better compression rate than that of the other compression method of the first compression method and a second compression method when the determination unit determines that the compression rate of the compressed data by the first compression method is better than the reference, and
• the output unit outputs data obtained by compressing the data by the compression method having a worse compression rate than that of the other compression method of the first compression method and the second compression method when the determination unit determines whether the compression rate of the data compressed by the first compression method is equal to or worse than the reference.

A method for compressing data in a storage system, comprising:

• compressing the data with a first compression method to generate compressed data;
• determining whether a compression rate of the compressed data compressed by the first compression method is better than a predetermined reference;
• outputting data obtained by compressing the data by the compression method having a better compression rate than that of the other compression method of the first compression method and a second compression method when it is determined that the compression rate of the compressed data compressed by the first compression method is better than the reference;
• and
• outputting data obtained by compressing the data by the compression method having a worse compression rate than that of the other compression method of the first compression method and the second compression method when it is determined that the compression rate of the compressed data compressed by the first compression method is equal to or worse than the reference.