METHOD AND APPARATUS FOR DECOMPOSING I/O TASKS IN A RAID SYSTEM

摘要

A data access request to a file system is decomposed into a plurality of lower-level I/O tasks. A logical combination of physical storage components is represented as a hierarchical set of objects. A parent I/O task is generated from a first object in response to the data access request. A child I/O task is generated from a second object to implement a portion of the parent I/O task. The parent I/O task is suspended until the child I/O task completes. The child I/O task is executed in response to an occurrence of an event that a resource required by the child I/O task is available. The parent I/O task is resumed upon an event indicating completion of the child I/O task. Scheduling of any child I/O task is not conditional on execution of the parent I/O task, and a state diagram regulates the child I/O tasks.

主权项

1. A method for processing data access requests at a storage system, comprising:
representing components of a RAID system of a storage operating system of the storage system as a set of objects, the storage operating system executed by a processor of the storage system; receiving a data access request at the storage system directed to the set of objects; decomposing the data access request to generate a parent I/O task and a child I/O task, wherein a hierarchical order is assigned to the parent I/O task and the child I/O task; associating a first set of parameters with the parent I/O task; associating second set of parameters with the child I/O task; and assigning the parent I/O task to a first object in the set of objects and the child I/O task to a second object in the set of objects.