System and method for dynamic allocation of unified cache to one or more logical units

摘要

A system and method provide a unified cache in a Small Computer System Interface (SCSI) device which can be dynamically allocated to one or more Logical Units (LUs). A cache balancer module of the SCSI device can allocate the entire unified cache to a single LU, or divide the unified cache among multiple LUs. The cache entries for each LU can be further classified based on Quality of Service (QoS) traffic classes within each LU thereby improving the QoS performance. The system provides a cache allocation table that maintains a unified cache allocation status for each LU.

主权项

1. A system, comprising:
a host device; and a SCSI device, wherein said SCSI device comprises:
a unified cache module,a cache allocation table, anda cache balancer module configured to:
allocate at least one cache slot in said unified cache module to at least one Logical Unit (LU) in response to receiving an input/output (I/O) request from said host device;log at least one cache entry by caching data for said received I/O request to said at least one cache slot of said unified cache; andregister a table entry corresponding to said allocated at least one cache slot into said cache allocation table of said at least one LU.