Data caching with a partially compressed cache

A method for effectively increasing data transfer bandwidth between a host system and a storage system, the method comprising:

• utilizing a system adapter in the storage system for storage data transfer, the system adapter including compression logic and decompression logic;
• coupling at least one partially compressed cache to the system adapter, the at least one partially compressed cache comprising an uncompressed partition and a compressed partition, the compressed partition storing compressed data from the uncompressed partition in a same storage location in the at least one partially compressed cache;
• and
• transferring data through the compression logic to the uncompressed partition to effectively increase data transfer from the system adapter to the partially compressed cache by a factor corresponding to a compression ratio of the compression logic.

A method for caching data in a multi-level caching arrangement of a data processing system, the method comprising:

• partitioning each cache level to include a compressed data partition and an uncompressed data partition;
• adjusting the compressed data partition and the uncompressed data partition of each cache level for chosen performance characteristics;
• and
• utilizing the compressed and uncompressed data partitions of each cache level to cache data from a storage device, the compressed partition storing compressed data from the uncompressed data partition in a same storage location as in the uncompressed data partition, wherein cache pollution is substantially avoided and a data requesting path becomes faster.