Method, device and computer program product for managing storage system

A device for managing a storage system, comprising:

• at least one processing unit;
• at least one memory coupled to the at least one processing unit and storing instructions for execution by the at least one processing unit, the instructions, when executed by the at least one processing unit, causing the device to perform actions comprising:
• in response to receiving an Input/Output (I/O) request for a first slice of a logic storage unit in a storage system, obtaining a first bitmap with respect to the logic storage unit, the logic storage unit being divided into a plurality of slices including the first slice, and one bit in the first bitmap indicating whether a cache function is enabled for a respective one of the plurality of slices;
• determining, based on the first bitmap, whether the cache function is enabled for the first slice;
• and
• in response to determining that the cache function is enabled for the first slice, processing the I/O request at least with a cache in the storage system;
• wherein the cache comprises a plurality of cache pages, and wherein processing the I/O request at least with the cache comprises:
• obtaining a second bitmap with respect to the logic storage unit, one bit in the second bitmap indicating whether one of the plurality of cache pages corresponding to a respective one of the plurality of slices is valid or not;
• determining, based on the second bitmap, whether a first cache page in the plurality of cache pages corresponding to the first slice is valid or not;
• and
• in response to determining that the first cache page is invalid, forwarding the I/O request to the logic storage unit for processing.

A computer program product having a non-transitory computer readable medium which stores a set of instructions to manage a storage system;

• the set of instructions, when carried out by a device, causing the device to perform a method of:
• in response to receiving an Input/Output (I/O) request for a first slice of a logic storage unit in the storage system, obtaining a first bitmap with respect to the logic storage unit, the logic storage unit being divided into a plurality of slices including the first slice, and one bit in the first bitmap indicating whether a cache function is enabled for a respective one of the plurality of slices;
• determining, based on the first bitmap, whether the cache function is enabled for the first slice;
• and
• in response to determining that the cache function is enabled for the first slice, processing the I/O request at least with a cache in the storage system;
• wherein the cache comprises a plurality of cache pages, and wherein processing the I/O request at least with the cache comprises:
• obtaining a second bitmap with respect to the logic storage unit, one bit in the second bitmap indicating whether one of the plurality of cache pages corresponding to a respective one of the plurality of slices is valid or not;
• determining, based on the second bitmap, whether a first cache page in the plurality of cache pages corresponding to the first slice is valid or not;
• and
• in response to determining that the first cache page is invalid, forwarding the I/O request to the logic storage unit for processing.