Method and apparatus for zeroing a transfer buffer memory as a background task

Abstract

A computer system that cleans buffer memory as a background task. The system includes a transfer buffer, a memory that stores an index or table indicating free and non-zero data sectors within the transfer buffer, and processing logic that uses the transfer buffer for data transfer operations, and when otherwise idle, that scans the index table for contiguous sections of free and non-zero data sectors of the transfer buffer and that zeroes at least one of the contiguous sections. The system allocates buffer memory and performs parallel logic operations into the buffer, such as XOR logic operations to generate new parity data. The buffer must first be zeroed or cleaned prior to the parallel operations. With the background task, the system is more likely to find an appropriate size buffer of free and zeroed data sectors in the transfer buffer to perform the parallel logic operations. The background task significantly reduces or relieves the system from having to issue CDB-based memory commands to zero or clean an allocated buffer during disk I/O operations.