Method and device for managing hash table, and computer program product

An apparatus for managing a hash table, comprising:

• at least one processing unit;
• at least one memory, the at least one memory is coupled to the at least one processing unit and stores instructions to be executed by the at least one processing unit, the instructions, when executed by the at least one processing unit, causing the apparatus to perform acts, the acts including:
• in response to receiving a write request, determining whether a first hash value associated with the write request is stored in a set of hash tables, the set of hash tables including at least a first hash table and a second hash table, the first hash table being a currently valid hash table for a first storage device, the second hash table being stored in a second storage device, an access speed of the first storage device being faster than that of the second storage device,
• in response to determining that the first hash value is not stored in the set of hash tables and the first hash table is full, setting a pre-allocated third hash table in the first storage device as the currently valid hash table for the first storage device,
• writing a first entry into the third hash table, the first entry including the first hash value, and
• merging entries in the first hash table with entries in the second hash table for storage into the second storage device.

A computer program product having a non-transitory computer readable medium which stores a set of instructions for managing a hash table;

• the set of instructions, when carried out by computerized circuitry, causing the computerized circuitry to perform a method of:
• in response to receiving a write request, determining whether a first hash value associated with the write request is stored in a set of hash tables, the set of hash tables including at least a first hash table and a second hash table, the first hash table being a currently valid hash table for a first storage device, the second hash table being stored in a second storage device, an access speed of the first storage device being faster than that of the second storage device;
• in response to determining that the first hash value is not stored in the set of hash tables and the first hash table is full, setting a pre-allocated third hash table in the first storage device as the currently valid hash table for the first storage device;
• writing a first entry into the third hash table, the first entry including the first hash value;
• and
• merging entries in the first hash table with entries in the second hash table for storage into the second storage device.