公开(公告)号：JPH09204338A

公开(公告)日：1997-08-05

申请号：JP888396

申请日：1996-01-23

Applicant: TANDEM COMPUTERS INC

Inventor： JIEEMUZU EI RAIAN ,  SUTEIIBUN AARU PIASON ,  FURANKO PUTSUTOZORU

IPC: G06F12/00

Abstract: PROBLEM TO BE SOLVED: To speed up the restoration of fault in a data processing system by scanning an interrupted operation record backward from a common log at the time of the occurrence of fault and writing a corresponding compensation log entry forward in the common log. SOLUTION: The common log is formed by the log synthesis of an independent resource manager. During restoring processing, this log is scanned in backward order, and a count value is increased and the entry of the compensation log is written forward in the log for every compensation operation. When the count value becomes equal to a present value, a next AND record is written forward in the log including the record-id of the present log record in the middle of compensation. Until the recode provided with record-id in the middle of next AND recording, all the record is neglected. Consequently, the entry of the compensation log of a next ANDed record within the log is neglected to prevent exceeding AND processing.

公开(公告)号：JPH0922384A

公开(公告)日：1997-01-21

申请号：JP862596

申请日：1996-01-22

Applicant: TANDEM COMPUTERS INC

Inventor： FURANKO PUTSUTOZORU

IPC: G06F12/00 ,  G06F12/08 ,  G06F15/163

Abstract: PROBLEM TO BE SOLVED: To secure reliability by distributing a cache. SOLUTION: Respective processors 12 maintain the cache for discriminating the states of the caching of respective files, the blocks of the respective files to be cached and cached open files. As long as only one processor opens the file and opens it for read/write access, the processor is allowed to perform read/write caching to the file. When the processor opens the file for the read access, the processor is allowed to perform read caching as long as the other processor does not open the file for the read/write access. After the last processor which performs the read/wire access to the file closes the file, a disk system upgrades a cache state to the file.