Prefill of raid stripes in a storage system by reading of existing data

A method comprising:

• configuring a storage system to include a plurality of storage nodes each comprising one or more storage devices, each of the storage nodes further comprising a processor coupled to a memory;
• reading data blocks from the one or more storage devices of a given one of the storage nodes;
• for a given one of the data blocks, determining based at least in part on a content-based signature of that data block whether or not the given data block is appropriate for use in a prefilling operation of the given storage node;
• responsive to the given data block being appropriate for use in the prefilling operation of the given storage node, using the data block in the prefilling operation of the given storage node;
• and
• responsive to the given data block not being appropriate for use in the prefilling operation of the given storage node, sending the data block to another one of the storage nodes for use in a prefilling operation of that other storage node.

A computer program product comprising a non-transitory processor-readable storage medium having stored therein program code of one or more software programs, wherein the program code when executed by a storage system comprising a plurality of storage nodes each comprising one or more storage devices, each of the storage nodes further comprising a processor coupled to a memory, causes the storage system:

• to read data blocks from the one or more storage devices of a given one of the storage nodes;
• for a given one of the data blocks, to determine based at least in part on a content-based signature of that data block whether or not the given data block is appropriate for use in a prefilling operation of the given storage node;
• responsive to the given data block being appropriate for use in the prefilling operation of the given storage node, to use the data block in the prefilling operation of the given storage node;
• and
• responsive to the given data block not being appropriate for use in the prefilling operation of the given storage node, to send the data block to another one of the storage nodes for use in a prefilling operation of that other storage node.