From: Andi Kleen Subject: Re: [PATCH] use unfair spinlock when running on hypervisor. Date: Tue, 01 Jun 2010 17:53:09 +0200 Message-ID: <87sk56ycka.fsf@basil.nowhere.org> References: <20100601093515.GH24302@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, avi@redhat.com, hpa@zytor.com, mingo@elte.hu, npiggin@suse.de, tglx@linutronix.de, mtosatti@redhat.com To: Gleb Natapov Return-path: In-Reply-To: <20100601093515.GH24302@redhat.com> (Gleb Natapov's message of "Tue\, 1 Jun 2010 12\:35\:15 +0300") Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org Gleb Natapov writes: > > The patch below allows to patch ticket spinlock code to behave similar to > old unfair spinlock when hypervisor is detected. After patching unlocked The question is what happens when you have a system with unfair memory and you run the hypervisor on that. There it could be much worse. Your new code would starve again, right? There's a reason the ticket spinlocks were added in the first place. -Andi -- ak@linux.intel.com -- Speaking for myself only.