Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 18 Sep 2002 13:58:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 18 Sep 2002 13:58:24 -0400 Received: from hq.fsmlabs.com ([209.155.42.197]:49368 "EHLO hq.fsmlabs.com") by vger.kernel.org with ESMTP id ; Wed, 18 Sep 2002 13:58:19 -0400 Date: Wed, 18 Sep 2002 12:00:04 -0600 From: yodaiken@fsmlabs.com To: Ingo Molnar Cc: Linus Torvalds , Rik van Riel , Andries Brouwer , William Lee Irwin III , linux-kernel@vger.kernel.org Subject: Re: [patch] lockless, scalable get_pid(), for_each_process() elimination, 2.5.35-BK Message-ID: <20020918120004.A13778@hq.fsmlabs.com> References:

Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: ; from mingo@elte.hu on Wed, Sep 18, 2002 at 07:54:53PM +0200 Organization: FSM Labs Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1536 Lines: 32 On Wed, Sep 18, 2002 at 07:54:53PM +0200, Ingo Molnar wrote: > or a phone line server that handles 100 thousand phone lines starts up > 100K threads, one per line. No need to restart any of those threads, and > in fact it will never happen. They do use helper threads to do less timing > critical stuff. Now the whole phone system locks up for 1.5 minutes every > 2 weeks or 2 months when the PID range overflows, how great. Now make that > 400 thousand phonelines, the lockup will will last 24 minutes. So Solaris made a stupid design decision to encourage people to use a thread per call on these big systems and Linux should make the same decision for compatibility? I can see why people want this: they have huge ugly systems that they would like to port to Linux with as little effort as possible. But it's not free for the OS either. It's interesting to see that as Linux moves into the phone space owned by Sun, two things are happening. (1)There is pressure to expand Linux to simply match Solaris properties and (2) the entire technological and business basis of those huge 100K+ thread racks is beginning to collapse. --------------------------------------------------------- Victor Yodaiken Finite State Machine Labs: The RTLinux Company. www.fsmlabs.com www.rtlinux.com - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/