Using an attribute of a write request to determine where to cache data in a storage system having multiple caches including non-volatile storage cache in a sequential access storage device

A computer program product for managing data in a sequential access storage device receiving read requests and write requests from a system with respect to tracks stored in a sequential access storage medium, the computer program product comprising a non-transitory computer readable storage medium having computer readable program code embodied therein that executes to perform operations, the operations comprising:

• caching received modified tracks in a non-volatile storage device integrated with the sequential access storage device in response to determining to cache the modified tracks;
• receiving a write request having modified tracks;
• determining whether an attribute of the received write request satisfies a condition;
• caching the received modified tracks for the write request in the non-volatile storage device in response to determining that the determined attribute does not satisfy the condition;
• adding a destage request to a request queue for the received write request having the determined attribute not satisfying the condition;
• and
• writing the received modified tracks for the write request having the determined attribute satisfying the condition at a higher priority than modified tracks for write requests having the attribute not satisfying the condition.