STORAGE SYSTEM FOR ATOMIC WRITE WHICH INCLUDES A PRE-CACHE

1 . A method of operating a storage system which includes a control layer, said control layer including a volatile memory and a volatile memory control module, said control layer operatively coupled to a physical storage space including a plurality of storage disk drives, the method comprising:

configuring said volatile memory into cache memory and pre-cache memory;

receiving an indication that a plurality of blocks relating to a command is to be written as an atomic write operation;

enabling tracking of said atomic write operation;

caching at least one block from said plurality in said pre-cache memory; and

upon receiving an indication that all blocks in said plurality have been successfully accommodated in said pre-cache memory, enabling data corresponding to said plurality of blocks to subsequently be cached in said cache memory and discontinuing tracking of said atomic write operation.

2 . The method of claim 1 , wherein a commit write command is said indication that all blocks have been successfully accommodated in said pre-cache memory.

3 . The method of claim 1 , wherein said enabling data corresponding to said plurality of blocks to subsequently be cached in said cache memory includes: moving said data to said cache memory.

4 . The method of claim 1 , wherein said enabling data corresponding to said plurality of blocks to subsequently be cached in said cache memory includes: reassigning memory blocks in said pre-cache memory which include said data to said cache memory.

5 . The method of claim 1 , further comprising:

upon receiving instead an indication that an event has occurred which precludes at least one block in said plurality from being successfully accommodated in said pre-cache memory, discarding data in said pre-cache memory which corresponds to said atomic write operation system and discontinuing tracking of said atomic write operation.

6 . The method of claim 5 , wherein said event includes a failure at an external host or in a connection with an external host port.

7 . The method of claim 1 , wherein said storage system communicates with an external host using an SCSI protocol.

8 . The method of claim 1 , wherein said enabling tracking includes: adding an entry for said atomic write operation to a table or other data structure which tracks active atomic write operations.

9 . A storage system, comprising:

a physical storage space including a plurality of storage disk drives;

a control layer including a volatile memory, and a volatile memory control module, said control layer operatively coupled to said physical storage space and operable to:

configure said volatile memory into cache memory and pre-cache memory;

receive an indication that a plurality of blocks relating to a command is to be written as an atomic write operation;

enable tracking of said atomic write operation;

cache at least one block from said plurality in said pre-cache memory; and

upon receipt of an indication that all blocks in said plurality have been successfully accommodated in said pre-cache memory, enable data corresponding to said plurality of blocks to subsequently be cached in said cache memory and discontinue tracking of said atomic write operation.

10 . The system of claim 9 , wherein a commit write command is said indication that all blocks have been successfully accommodated in said pre-cache memory.

11 . The system of claim 9 , wherein operable to enable data corresponding to said plurality of blocks to subsequently be cached in said cache memory includes:

operable to move said data to said cache memory.

12 . The system of claim 9 , wherein operable to enable data corresponding to said plurality of blocks to subsequently be cached in said cache memory includes:

operable to reassign memory blocks in said pre-cache memory which include said data to said cache memory.

13 . The system of claim 9 , wherein said control layer is further operable to:

upon receipt instead of an indication that an event has occurred which precludes at least one block in said plurality from being successfully accommodated in said pre-cache memory, discard data in said pre-cache memory which corresponds to said atomic write operation and discontinue tracking of said atomic write operation.

14 . The system of claim 13 , wherein said event includes a failure at an external host or in a connection with a host port.

15 . The system of claim 9 , wherein said control layer is operable to communicate with an external host using an SCSI protocol.

16 . The system of claim 9 , wherein operable to enable tracking includes: operable to add an entry for said atomic write operation to a table or other data structure which tracks active atomic write operations.

17 . A computer program product comprising a non-transitory computer usable medium having computer readable program code embodied therein for operating a storage system which includes a control layer, said control layer including a volatile memory and a volatile memory control module, said control layer operatively coupled to a physical storage space including a plurality of storage disk drives, the computer program product comprising:

computer readable program code for causing the computer to configure said volatile memory into cache memory and pre-cache memory;

computer readable program code for causing the computer to receive an indication that a plurality of blocks relating to a command is to be written as an atomic write operation;

computer readable program code for causing the computer to enable tracking of said atomic write operation;

computer readable program code for causing the computer to cache at least one block from said plurality in said pre-cache memory; and

computer readable program code for causing the computer, upon receiving an indication that all blocks in said plurality have been successfully accommodated in said pre-cache memory, to enable data corresponding to said plurality of blocks to subsequently be cached in said cache memory and to discontinue tracking of said atomic write operation.