From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailserv2.iuinc.com (IDENT:qmailr@mailserv2.iuinc.com [206.245.164.55]) by puffin.external.hp.com (8.9.3/8.9.3) with SMTP id RAA05651 for ; Sun, 17 Dec 2000 17:28:27 -0700 From: Stan Sieler Message-Id: <200012180029.QAA03444@opus.allegro.com> Subject: Re: [parisc-linux] ldcw in __pthread_acquire To: alan@lxorguk.ukuu.org.uk (Alan Cox) Date: Sun, 17 Dec 2000 16:29:50 -0800 (PST) Cc: matthew@wil.cx (Matthew Wilcox), jes@linuxcare.com (Jes Sorensen), alan@linuxcare.com.au (Alan Modra), jsm@udlkern.fc.hp.com (John Marvin), parisc-linux@thepuffingroup.com In-Reply-To: from "Alan Cox" at Dec 17, 2000 02:38:10 AM MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii List-ID: Re: > There are good reasons for doing buzzlocks in user space Not really...they all vanish when you look with the microscope of experience. Trust me. I've been doing this stuff (multi-processor, semaphores, locks, etc.) for 30 years. And, Lamont agrees, apparently :) (Thanks, Lamont, and hi!) The apparent advantages are *strictly* short term. A single mistake using a buzz lock from user code in a single process on a single computer can cost more time than all properly implemented buzz locks ever save. The "it's faster" argument is the same kind of argument as "not indenting my code makes it faster to write, because I don't have to waste the time pressing that space bar or tab key"....and precisely as bad an argument :) Operating system functions, strangely enough, deserved to be implemented in the *operating system*! Gaining exclusive access to a data structure is such a function. -- Stan Sieler sieler@allegro.com www.allegro.com/sieler/wanted/index.html www.sieler.com