From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Wedgwood Date: Fri, 26 Mar 2004 23:41:10 +0000 Subject: Re: should ia64_spinlock_contention do backoff? Message-Id: <20040326234110.GA27824@dingdong.cryptoapps.com> List-Id: References: <200403251941.i2PJfrTH026392@napali.hpl.hp.com> In-Reply-To: <200403251941.i2PJfrTH026392@napali.hpl.hp.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org On Fri, Mar 26, 2004 at 09:16:52AM -0800, markw@osdl.org wrote: > We have 4-way Itanium2 systems here. Is that large enough for > testing? It depends on the level of lock contention and what the remote memory latency is (well, essentially how quickly you can bounce cachelines about). As other people have mentioned SGI has tested this on much larger configurations without seeing much incentive to use it. As a general principal I think getting lock contention down is more worthwhile (but very much harder usually). Does anyone have any idea what locks are most heavily contented for ia64 right now? John? --cw