Patent · US Expired

Method and system for controlling recovery downtime

US6351754B1 · kind B1 · utility

66Cited by
8References
61Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 23, 1998
Grant dateFeb 26, 2002
Priority date
Expiry dateJun 23, 2018

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S707/99953
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method and system for reducing overhead associated with recovering after a failure. According to the method, a checkpoint value is maintained that indicates which records of a plurality of records have to be processed after the failure. The plurality of records contain change information that corresponds to a plurality of data blocks. A target checkpoint value is determined based on a desired number of data block reads that will be required during a redo phase of recovery. Changes contained in volatile memory are then written to nonvolatile memory to advance the checkpoint value to at least the target checkpoint value. According to another aspect of the invention, the target checkpoint value is determined using a circular queue of offset buckets. The offset buckets are used to store index values that are associated with buffers in the ordered list. The target checkpoint value is periodically set equal to an index value that is contained in an offset bucket. According to another aspect of the invention, the target checkpoint value is determined by calculating a maximum number of records that should be processed after the failure. The maximum number of records is based on the desir…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.