Patent Number: 7,765,361

Title: Enforced transaction system recoverability on media without write-through

Abstract: To ensure that logs representative of data changes are durably written, localized storage media cache is flushed to force a write to stable storage. Log sequence number tracking is leveraged to determine if log data in a localized storage media cache is likely to have not been written to durable storage. When this condition is likely, a FLUSH_CACHE command is issued to a storage media controller to force a durable write. This allows recovery of data changes to a transactional system even when its associated storage media does not provide write-ordering guarantees. Moreover, flushing of the storage media cache can be accomplished at a frequency that provides an upper bound on a maximum time between a transaction commit and data being made durable.

Inventors: Dhamankar; Robin Dhananjay (Redmond, WA), Kathuria; Vishal (Woodinville, WA), Kalavakur; Sethu (Redmond, WA), Venkataraman; Gayathri (Redmond, WA), Levy; Avraham (Seattle, WA), Kodavalla; Hanumantha Rao (Sammamish, WA), Li; Chunjia (Issaquah, WA), Christensen; Eric Ray (Redmond, WA)

Assignee: Microsoft Corporation

International Classification: G06F 12/16 (20060101)

Expiration Date: 7/27/12018