Use of flash cache to improve tiered migration performance

A system for data processing in a computing storage environment, the computing storage environment incorporating at least high-speed and lower-speed caches, and tiered levels of storage, comprising:

• a processor device, operable in the computing storage environment, wherein the processor device:
• at a time in which at least one data segment is to be migrated from one level to another level of the tiered levels of storage, initiates a data migration mechanism by:
• copying data resident in the lower-speed cache corresponding to the at least one data segment to be migrated to a target on the another level, and
• reading remaining data, not previously copied from the lower-speed cache, from a source on the one level, and writing the remaining data to the target.

A computer program product for data processing in a computing storage environment by a processor device, the computing storage environment incorporating at least high-speed and lower-speed caches, and tiered levels of storage, the computer program product comprising a non-transitory computer-readable storage medium having computer-readable program code portions stored therein, the computer-readable program code portions comprising:

• a first executable portion that:
• at a time in which at least one data segment is to be migrated from one level to another level of the tiered levels of storage, initiates a data migration mechanism by:
• copying data resident in the lower-speed cache corresponding to the at least one data segment to be migrated to a target on the another level, and
• reading remaining data, not previously copied from the lower-speed cache, from a source on the one level, and writing the remaining data to the target.