Disk drive controller incorporating task manager for reducing performance spikes

An apparatus, comprising:

• a disk drive comprising non-volatile rotatable media and configured to communicate with a host system, the disk drive comprising:
• a controller operatively coupled to the non-volatile rotatable media, the controller configured to receive a series of host commands to be executed by the controller and generate a command execution sequence comprising the series of host commands;
• and
• a task manager integral or coupled to the controller, the task manager configured to:
• receive a plurality of background tasks comprising at least two priority background tasks to be executed by the controller along with execution of the series of host commands;
• and
• insert one or more of the at least two priority background tasks into the command execution sequence while maintaining a specified ratio of priority background task execution and host command execution substantially constant;
• wherein the controller is configured to execute the command execution sequence with the one or more inserted priority background tasks, and the task manager is configured to adjust the specified ratio of priority background task execution and host command execution in response to changes in priority background task workload.

An apparatus, comprising:

• a data storage system configured to communicate with a host system, the data storage system comprising:
• at least one disk drive comprising non-volatile rotatable media;
• a controller operatively coupled to the disk drive and configured to receive commands from the host system including read/write commands and to execute background tasks including priority background tasks, the background tasks defining operations performed by the controller distinct from controller operations responsive to the commands received from the host system;
• and
• a task manager integral or coupled to the controller, the task manager configured to:
• limit a number of priority background tasks executed by the controller in terms of estimated completion time within a time interval during which the controller is actively executing read/write commands received from the host system;
• maintain a specified ratio of priority background task execution and read/write command execution substantially constant;
• and
• adjust the specified ratio of priority background task execution and read/write command execution in response to changes in priority background task workload.