Data storage controller

A non-transitory computer-readable storage medium storing instructions which, when executed by one or more processors, cause the one or more processors to perform operations comprising:

• receiving a host write request for a logical drive corresponding to a redundant array of physical drives, wherein the redundant array of physical drives comprises a first physical drive of a first drive type and a second physical drive of a second drive type different from the first drive type, and wherein data stored on the first physical drive is mirrored on the second physical drive;
• generating and issuing a first input-output (IO) request for the first physical drive based on the host write request and a write-through cache policy associated with the first drive type;
• and
• generating and issuing a second IO request for the second physical drive based on the host write request and a write-back cache policy associated with the second drive type.

A data storage system, comprising:

• a redundant array of physical drives including a solid-state drive (SSD) and a hard disk drive (HDD), wherein data stored on the SSD is mirrored on the HDD;
• and
• a data storage controller configured to execute host input-output (IO) requests in the redundant array of physical drives, wherein the data storage controller comprises:
• a computer-readable storage medium storing one or more sequences of instructions;
• and
• one or more processors configured to execute the one or more sequences of instructions to:
• receive a host write request for a logical drive corresponding to the redundant array of physical drives;
• generate and issue a first IO request for the SSD based on the host write request and a first cache policy associated with the SSD;
• and
• generate and issue a second IO request for the HDD based on the host write request and a second cache policy associated with the HDD,
• wherein the first cache policy is different from the second cache policy.