Patent ID: 8356126

Claim:
A redundant array of inexpensive disks (RAID) controller for efficiently transferring data with a redundant array of physical disks, comprising: a memory, for storing for each of the physical disks a queue of commands to issue to the physical disk, wherein a portion of said commands in said queues specify user data specified by a host computer to be transferred with the physical disks, and a portion of said commands, generated by the RAID controller independent of host computer I/O requests, specify redundancy data to be transferred with the physical disks; and a processor, coupled to said memory, configured to execute coalescer code configured to receive command completions from the physical disks, and in response thereto, for each of the physical disks to: coalesce into a single command two or more of said commands in said queue that have a same read/write type and specify adjacent locations on the physical disk; and issue to the physical disk said single coalesced command.