US Patent 10447296 Accelerated compression/decompression including predefined dictionary

A computer system includes a hardware controller and an internal millicode storage area. The controller includes an accelerator that decompresses a data stream requested by an application. The internal millicode storage area can store a compression dictionary library including a plurality of different pre-defined compression dictionaries. A host system includes a dictionary manager that determines a compression dictionary from the plurality of different pre-defined compression dictionaries included in the dictionary library to decompress the data stream. The accelerator can access the internal millicode storage area to obtain the determined compression dictionary, and to decompress the data stream according to the determined compression dictionary.