公开(公告)号：DE69734432T2

公开(公告)日：2006-07-13

申请号：DE69734432

申请日：1997-12-11

Applicant: IBM

Inventor： FREUND THOMAS ,  HOLDSWORTH SIMON ANTONY JAMES ,  HOUSTON IAIN STUART CALDWELL

IPC: H04L29/06 ,  G06F9/50

Abstract: An apparatus for dispatching client requests within a server computer system, wherein the client requests are issued from at least one client computer system on a different platform from said server computer system and are passed through a communications channel to said server computer system, the apparatus comprising: a buffer having an input connected to said communications channel and an output; a plurality of parallel execution threads connected to said output of said buffer; and a scheduling means for distributing client requests stored in said buffer to said plurality of execution threads in a manner such that related client requests are sent to the same execution thread.

公开(公告)号：DE69530252D1

公开(公告)日：2003-05-15

申请号：DE69530252

申请日：1995-08-22

Applicant: IBM

Inventor： COBB EDWARD ELLIS ,  HOLDSWORTH SIMON ANTONY JAMES ,  HOUSTON IAIN STUART CALDWELL ,  SMITH STANLEY ALAN

IPC: G06F12/00 ,  G06F9/46 ,  G06F15/00

Abstract: A system and method for reducing message traffic during two phase commitment in a distributed transaction processing system. Transactional objects manage transactions in a distributed system. A coordinator object is responsible for ensuring data consistency by enforcing atomic transaction changes. Any change to one or more resources by a transaction is either made at all or none of the resources. Distributed transactions use interposition to create subordinate coordinator for domains other than the primary domain. Each subordinate coordinator controls transaction commitment of all resources within that domain via a single message sequence per coordinator. Dynamic registration of subordinate coordinator resources ensures that the subordinate coordinator is not added to the commit tree of the root coordinator unless it has recoverable resources. Dynamic registration minimizes the size of the commit tree thereby minimizing the number of messages transmitted during commitment processing.

公开(公告)号：GB2327134B

公开(公告)日：2002-04-03

申请号：GB9714330

申请日：1997-07-08

Applicant: IBM

Inventor： HOLDSWORTH SIMON ANTONY JAMES ,  HOUSTON IAIN STUART CALDWELL

IPC: G06F9/46

Abstract: A server concurrency control technique for use in a client/server computing system where a client sends a request to a server for access to a server resource involves receiving client requests of a plurality of lock requester types at a lock requester interface; comparing each of said requests against a lock requester set which has a lock requester type representation corresponding to a lock requester type of previously received client requests which are presently holding locks to server resources; and as a result of the comparing step, determining whether a newly received client request conflicts with previously received client requests which are currently holding locks to server resources.

公开(公告)号：GB2334117A

公开(公告)日：1999-08-11

申请号：GB9802298

申请日：1998-02-04

Applicant: IBM

Inventor： FREUND THOMAS ,  HOUSTON IAIN STUART CALDWELL

IPC: G06F15/16 ,  G06F9/46 ,  G06F9/52 ,  G06F15/177

Abstract: An apparatus for dispatching client requests for execution by a server object in a heterogeneous object-oriented client/server computing environment, has: a request-holding buffer (in 32) having an input connected to a communications channel receiving the client requests, and an output connected to a plurality of parallel execution threads 33a-c; and a semantic concurrency control means 34 for examining the semantics of a request in the buffer and the semantics of each request presently being executed on any of the threads, and for delaying the request from being dispatched from the buffer to a thread if the examined semantics of the requests indicate that such dispatch would cause conflicting access to the server object's resources.

公开(公告)号：GB2327134A

公开(公告)日：1999-01-13

申请号：GB9714330

申请日：1997-07-08

Applicant: IBM

Inventor： HOLDSWORTH SIMON ANTONY JAMES ,  HOUSTON IAIN STUART CALDWELL

IPC: G06F9/46

Abstract: Different types of client requests for access to server objects produce corresponding lock requesters. A new access request results in a new lock request which is compared with existing lock requesters for the existing server access requests. If the new lock request does not conflict with the existing ones then the access request is permitted. If there is conflict between the lock requests then this is resolved using a server concurrency unit.