From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 28 May 2002 11:50:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 28 May 2002 11:50:09 -0400 Received: from gateway-1237.mvista.com ([12.44.186.158]:63739 "EHLO hermes.mvista.com") by vger.kernel.org with ESMTP id ; Tue, 28 May 2002 11:50:08 -0400 Subject: Re: 8-CPU (SMP) #s for lockfree rtcache From: Robert Love To: dipankar@in.ibm.com Cc: "David S. Miller" , Linus Torvalds , linux-kernel@vger.kernel.org, Paul McKenney , Andrea Arcangeli In-Reply-To: <20020528182806.A21303@in.ibm.com> Content-Type: text/plain Content-Transfer-Encoding: 7bit X-Mailer: Ximian Evolution 1.0.3 (1.0.3-6) Date: 28 May 2002 08:49:58 -0700 Message-Id: <1022600998.20317.44.camel@sinai> Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2002-05-28 at 05:58, Dipankar Sarma wrote: > > Thanks, I am convinced RCU is the way to go. I am not. :P > Well, the last time RCU was discussed, Linus said that he would > like to see someplace where RCU clearly helps. I agree the numbers posted are nice, but I remain skeptical like Linus. Sure, the locking overhead is nearly gone in the profiled function where RCU is used. But the overhead has just been _moved_ to wherever the RCU work is now done. Any benchmark needs to include the damage done there, too. I also balk at implicit locking... Robert Love