Method, device and computer program product for managing raid

A device for managing redundant arrays of independent drives (RAID), comprising:

• at least one processor;
• and
• a memory coupled with the at least one processor, the memory including an instruction stored therein, the instruction, when executed by the at least one processor, causing the device to execute acts of:
• in response to a target stripe to be built in the RAID, determining, from a resource pool, whether there are spare extents associated with at least one system disk;
• in response to determining that there are the spare extents associated with at least one system disk, determining an adjacent relationship of used extents associated with the at least one system disk within a RAID stripe;
• and
• determining, based on the adjacent relationship and the spare extents, an extent for building the target stripe.

A computer program product having a non-transitory computer readable medium which stores a set of instructions to manage redundant arrays of independent disks (RAID);

• the set of instructions, when carried out by computerized circuitry, causing the computerized circuitry to perform a method of:
• in response to a target stripe to be built in the RAID, determining, from a resource pool, whether there are spare extents associated with at least one system disk;
• in response to determining that there are the spare extents associated with at least one system disk, determining an adjacent relationship of used extents associated with the at least one system disk within a RAID stripe;
• and
• determining, based on the adjacent relationship and the spare extents, an extent for building the target stripe.