System and method for canceling write back operation during simultaneous snoop push or snoop kill operation in write back caches

A method for improving cache performance in a cache memory comprising a plurality of cache lines comprising at least a first cache line and a second cache line, the method comprising:

• receiving a read request comprising requested data;
• determining whether the requested data is stored in the cache memory;
• in the event that the requested data is not stored in the cache memory, determining whether the cache memory is full;
• in the event that the cache memory is full, selecting the first cache line as a victim cache line from among the plurality of cache lines;
• determining whether the first cache line is modified;
• in the event the first cache line is modified, determining whether a write back is required;
• in the event a write back is required, determining whether there is a pending snoop operation on the first cache line;
• in the event there is a pending snoop on the first cache line, cancelling the required write back;
• in the event a write back is required, determining whether there is a pending snoop operation on at least the second cache line;
• and
• in the event there is a pending snoop on the second cache line, cancelling the required write back.

A computer program product for improving cache performance in a cache memory comprising a plurality of cache lines comprising at least a first cache line and a second cache line, the computer program product having a computer-readable storage medium with a computer program embodied thereon, the computer program comprising:

• computer program code for receiving a read request comprising requested data;
• computer program code for determining whether the requested data is stored in the cache memory;
• computer program code for, in the event that the requested data is not stored in the cache memory, determining whether the cache memory is full;
• computer program code for, in the event that the cache memory is full, selecting the first cache line as a victim cache line from among the plurality of cache lines;
• computer program code for determining whether the first cache line is modified;
• computer program code for, in the event the first cache line is modified, determining whether a write back is required;
• computer program code for, in the event a write back is required, determining whether there is a pending snoop operation on the first cache line;
• computer program code for, in the event there is a pending snoop on the first cache line, cancelling the required write back;
• computer program code for, in the event a write back is required, determining whether there is a pending snoop operation on at least the second cache line;, and computer program code for, in the event there is a pending snoop on the second cache line, cancelling the required write back.