Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/5/84; site tolerant.UUCP
Path: utzoo!watmath!clyde!burl!ulysses!bellcore!decvax!ittatc!dcdwest!sdcsvax!ucbvax!hplabs!oliveb!tolerant!berry
From: berry@tolerant.UUCP (David W. Berry)
Newsgroups: net.sources
Subject: Re: P & V Algorithms needed
Message-ID: <299@tolerant.UUCP>
Date: Fri, 7-Mar-86 16:46:43 EST
Article-I.D.: tolerant.299
Posted: Fri Mar  7 16:46:43 1986
Date-Received: Mon, 10-Mar-86 00:17:50 EST
References: <2000005@ndm20>
Reply-To: berry@handel.UUCP (David W. Berry)
Organization: Tolerant Systems, Inc.  San Jose, CA
Lines: 27
Summary: Use Dekker's algorithm for P&V operations

In article <2000005@ndm20> lvs@ndm20 writes:
>
>In  an  effort  to  implement a  recoverable locking  mechanism for a
>database  across  a  wide range  of machines  I need  an algorithm to
>implement the standard P & V  operators ...

One possible solution, although is intended for usage in a common
memory environment, is Dekker's algorithm.  The original publishing
was of an algoritm to implement true locking on a two processor
system and was published in CACM some years ago.  There was also a
later issue of CACM which published corrections to the algorithm
and a yet later issue which presented a modification of the algorithm
that was generalized for N processors.

Sorry I can't give you more information but I implemented it several
years ago from somebody else's issue of CACM.


	David
-- 

	David W. Berry
	dwb@well.UUCP
	Delphi: dwb
	{ucbvax,pyramid,idsvax,bene,oliveb}!tolerant!berry

	I'm only here for the beer.