公开(公告)号：CA2353017A1

公开(公告)日：2003-01-12

申请号：CA2353017

申请日：2001-07-12

Applicant: IBM CANADA

Inventor： LI JOHN ,  HURAS MATTHEW A ,  SACHEDINA AAMER ,  ROMANUFA KERILEY K ,  SCHLAMB KELLY W ,  ZHENG ROGER L

IPC: G06F3/06 ,  G06F11/14 ,  G06F11/20 ,  G06F17/30 ,  G11B27/10 ,  G11B25/04

公开(公告)号：CA2322604C

公开(公告)日：2005-06-28

申请号：CA2322604

申请日：2000-10-06

Applicant: IBM CANADA

Inventor： XUE XUN ,  ZHENG ROGER L ,  VINCENT TIMOTHY J ,  MCKEOUGH SEAN W ,  HURAS MATTHEW A

IPC: G06F9/46 ,  G06F17/30

Abstract: A deadlock management system for a demultiplexed database system having work er agents and applications associated with and disassociated from the worker agents. Applications holding locks on database resources and capable of retaining locks when disassociated from worker agents. Providing each application with a flag set in accordance with the existing value of the application flag and in accordance with the state of applications holding and requesting locks. The deadlock management system providing for applications to be placed on a wait queue, a priority queue, or provided worker agents or overflow worker agents depending on the flag value for the application. Declaring deadlocks based on the flag value of applications and on the state of the lock wait graph showing applications holding and requesting locks.

公开(公告)号：CA2322604A1

公开(公告)日：2002-04-06

申请号：CA2322604

申请日：2000-10-06

Applicant: IBM CANADA

Inventor： XUE XUN ,  MCKEOUGH SEAN W ,  VINCENT TIMOTHY J ,  HURAS MATTHEW A ,  ZHENG ROGER L

IPC: G06F9/46 ,  G06F17/30

Abstract: A deadlock management system for a demultiplexed database system having work er agents and applications associated with and disassociated from the worker agents. Applications holding locks on database resources and capable of retaining locks when disassociated from worker agents. Providing each application with a flag set in accordance with the existing value of the application flag and in accordance with the state of applications holding and requesting locks. The deadlock management system providing for applications to be placed on a wait queue, a priority queue, or provided worker agents or overflow worker agents depending on the flag value for the application. Declaring deadlocks based on the flag value of applications and on the state of the lock wait graph showing applications holding and requesting locks.

公开(公告)号：CA2353017C

公开(公告)日：2004-03-16

申请号：CA2353017

申请日：2001-07-12

Applicant: IBM CANADA

Inventor： SCHLAMB KELLY W ,  ZHENG ROGER L ,  HURAS MATTHEW A ,  LI JOHN ,  ROMANUFA KERILEY K ,  SACHEDINA AAMER

IPC: G06F3/06 ,  G06F11/14 ,  G06F11/20 ,  G06F17/30 ,  G11B27/10 ,  G11B25/04

Abstract: Writes to a disk by a set of application processes in a database management system are managed. The database management system provides data buffering, direct disk access and asynchronous tasks for managing the data buffering. Each application process seeking to write to the disk acquires a disk latch in SHARED mode before writing to the disk and releases the disk latch following completion of the write to the disk. A user process is able to suspend disk writes by issuing a pause command to asynchronous tasks and acquiring the disk latch i n EXCLUSIVE mode. The user process resumes disk writes by issuing a resume command to the asynchronous tasks and releasing the disk latch.