公开(公告)号：CA2369621C

公开(公告)日：2009-06-09

申请号：CA2369621

申请日：2002-01-25

Applicant: IBM CANADA

Inventor： WINER MICHAEL J ,  ZHENG ROGER L Q ,  HURAS MATTHEW A ,  GOSS JEFFREY J ,  FLASZA MIROSLAW A ,  POSNER SARAH ,  MEADOWCROFT LORYSA M ,  MCARTHUR CATHERINE S

IPC: G06F9/50 ,  G06F9/46 ,  G06F12/00 ,  G06F12/14 ,  G06F13/14 ,  G06F17/30

Abstract: The present invention is directed at a method and apparatus for handling resource transaction requests. By marking a waiting transaction request, having an access mode which is incompatible with the access mode of at least one of the executing transactions, with an ignore bit, a subsequent transaction request with an access mode compatible with the access mode(s) o f the executing transaction(s) may receive access to the resource. The subsequent transactio n request is then marked with a bypass indicator such that when the executing transactions are finish ed accessing the resource, the waiting transaction request may be notified it may have access to the resource. By including the ignore bit, each subsequent transaction request which arrives after ignore b it has been set, does not suffer from starvation.

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.

公开(公告)号：CA2422176C

公开(公告)日：2009-07-21

申请号：CA2422176

申请日：2003-03-14

Applicant: IBM CANADA

Inventor： ZHENG ROGER L Q ,  MCINNIS DALE M ,  WINER MICHAEL J ,  MCARTHUR CATHERINE S ,  HURAS MATTHEW A ,  GOSS JEFFREY J ,  ROMANUFA KERILEY K

IPC: G06F16/11

Abstract: A method and system for suspending log-based updating of a database in a manner that permits its resumption without restore, to permit efficient alternation between a log-based update mode and a database access mode. Unplayed log records are protected, as re versions of database pages at a time when the log-based update was suspended. This permits log-based updating to resume where it left off. In order to ensure consistent data for access, a roll-back procedure creates consistent data pagers that are us ed for access, and discarded when log-based update resumes.

公开(公告)号：CA2422176A1

公开(公告)日：2004-09-14

申请号：CA2422176

申请日：2003-03-14

Applicant: IBM CANADA

Inventor： HURAS MATTHEW A ,  MCINNIS DALE M ,  WINER MICHAEL J ,  MCARTHUR CATHERINE S ,  GOSS JEFFREY J ,  ZHENG ROGER L Q ,  ROMANUFA KERILEY K

IPC: G06F16/11 ,  G06F17/30 ,  G06F17/40

Abstract: A method and system for suspending log-based updating of a database in a manner that permits its resumption without restore, to permit efficient alternation between a log-based update mode and a database access mode. Unplayed log records are protected, as re versions of database pages at a time when the log-based update was suspended. This permits log-based updating to resume where it left off. In order to ensure consistent data for access, a roll-back procedure creates consistent data pagers that are used for access, and discarded when log-based update resumes.

公开(公告)号：CA2419883A1

公开(公告)日：2004-08-26

申请号：CA2419883

申请日：2003-02-26

Applicant: IBM CANADA

Inventor： OFER EFFI ,  WINER MICHAEL J ,  HURAS MATTHEW A ,  ZHENG ROGER L Q ,  MCINNIS DALE M

IPC: G06F17/30

Abstract: A system and method for selectively processing log files for enhancing performance of table space recovery by processing only those log files required, as well as choosing which log file to process during recovery for both redo and rollback phases of recover y. The system and method skips the processing of log files that do not contain records of interest for the table space being recovered and determines whether a log file contains anything that nee ds to be played, in particular for the recovery of a subsystem in the database, such as a table space. Pre processing of the log files is not done, rather including tablespace ID correlated with log file ID information is collected while the log files are created. The cross-correlated informati on is used during tablespace recovery to selectively determine which of the log files to process. Some log files may be skipped in cases where not all of the database system is being recovered. A sub set of the database can be recovered, such as a tablespace, and which log files to process is determined based on lock intent.

公开(公告)号：CA2369621A1

公开(公告)日：2003-07-25

申请号：CA2369621

申请日：2002-01-25

Applicant: IBM CANADA

Inventor： POSNER SARAH ,  FLASZA MIROSLAW A ,  WINER MICHAEL J ,  ZHENG ROGER L Q ,  HURAS MATTHEW A ,  GOSS JEFFREY J ,  MEADOWCROFT LORYSA M ,  MCARTHUR CATHERINE S

IPC: G06F9/46 ,  G06F12/00 ,  G06F12/14 ,  G06F13/14 ,  G06F17/30

Abstract: The present invention is directed at a method and apparatus for handling resource transaction requests. By marking a waiting transaction request, having an access mode which is incompatible with the access mode of at least one of the executing transactions, with an ignore bit, a subsequent transaction request with an access mode compatible with the access mode(s) of the executing transaction(s) may receive access to the resource. The subsequent transaction request is then marked with a bypass indicator such that when the executing transactions are finished accessing the resource, the waiting transaction request may be notified it may have access to the resource. By including the ignore bit, each subsequent transaction request which arrives after ignore bit has been set, does not suffer from starvation.