公开(公告)号：CA2426606A1

公开(公告)日：2004-10-25

申请号：CA2426606

申请日：2003-04-25

Applicant: IBM CANADA

Inventor： MCARTHUR CATHERINE S ,  HURAS MATTHEW A ,  THORNBOROUGH SHAUN K ,  WINER MICHAEL J ,  HONG QUANHUA CLAIRE ,  ZHENG ROGER L Q ,  MEADOWCROFT LORYSA M

IPC: G06F16/901 ,  G06F17/30 ,  G06F12/02 ,  G06F17/40

Abstract: The present invention is directed to using a memory buffer to facilitate log catchup for online operations. Some designated areas of memory are allocated for one or more buffers for use during online operations (e.g. reorganization, create index, etc.). Concurrent update activities to the target object write informational records into the one or more buffer s. If the buffers become full, the informational records may be written to logs for persistent storage. After online operations finish building all or a suitable portion of the shadow object, l og catchup is performed by first applying activities in the informational records from the buffer an d thereafter applying activities from logs, if necessary. The invention helps solve the drawbacks of log catchup since the buffer contains only the information related to the target shadow object . Also it does not involve physical I/Os, as these records are all in memory.