Patent Number: 6,170,042

Title: Disc drive data storage system and method for dynamically scheduling queued commands

Abstract: A data storage system and method of scheduling commands in such a data storage system are provided in which commands are stored in a command sort queue and a scheduled command queue. Commands in the command sort queue are sorted and assigned a priority. Eventually, commands in the command sort queue are transferred to the scheduled command queue. Commands in the scheduled command queue are executed without further sorting. The desired queue depth or size of the scheduled command queue is determined as a function of both the queue depth of the command sort queue and a command execution rate value which is indicative of the rate at which commands in the scheduled command queue are executed. The desired queue depth may be dynamically determined using the queue depth of the command sort queue and the command execution rate value as inputs to a look-up table. The data storage system may include a small computer system interface (SCSI) disc (or "disk") drive which executes commands from a host system.

Inventors: Gaertner; Mark A. (Woodbury, MN), Heath; Mark A. (Oklahoma City, OK), Pruett; David C. (Oklahoma City, OK)

Assignee: Seagate Technology LLC

International Classification: G06F 3/06 (20060101); G06F 013/00 (); G06F 007/00 ()

Expiration Date: 01/02/2018