Patent ID: 6467023
Filing Date: 2002-10-15
Classification: G06F

Abstract:
A method operable in a RAID storage system for enabling immediate access to said RAID storage system comprising the steps of:creating a RAID level 5 logical unit within said RAID storage system; initializing said logical unit in response to creation of said logical unit; processing I/O requests directed to said logical unit in parallel with the step of initializing, wherein the step of initializing comprises steps of maintaining a boundary parameter value indicative of the progress of the initialization of said logical unit wherein said boundary parameter value indicates a physical position in said logical unit above which initialization is complete and below which initialization is incomplete, saving checkpoint data periodically during processing of the step of initializing indicative of progress of the step of initializing, interrupting processing of the step of initializing, and resuming the step of initializing using said checkpoint data, and the step of processing comprises steps of determining whether an I/O request to be processed includes access to storage space of said logical unit below said boundary parameter value, processing said I/O request normally in response to determining that said I/O request does not include access to storage space below said boundary parameter value, processing said I/O request in a manner so as to assure integrity of redundancy information associated with data of said I/O request in response to determining that said I/O request requires access to storage space below said boundary parameter value, requeuing said I/O request for later processing in response to a determination that the data to be accessed crosses said boundary parameter value.