From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with SMTP id D6D226008C6 for ; Tue, 24 Aug 2010 05:04:47 -0400 (EDT) Message-ID: <4C738B23.6040205@redhat.com> Date: Tue, 24 Aug 2010 12:04:35 +0300 From: Avi Kivity MIME-Version: 1.0 Subject: Re: [PATCH v5 08/12] Inject asynchronous page fault into a guest if page is swapped out. References: <1279553462-7036-1-git-send-email-gleb@redhat.com> <1279553462-7036-9-git-send-email-gleb@redhat.com> <4C729F10.40005@redhat.com> <20100824075258.GX10499@redhat.com> In-Reply-To: <20100824075258.GX10499@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Gleb Natapov Cc: kvm@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, mingo@elte.hu, a.p.zijlstra@chello.nl, tglx@linutronix.de, hpa@zytor.com, riel@redhat.com, cl@linux-foundation.org, mtosatti@redhat.com List-ID: On 08/24/2010 10:52 AM, Gleb Natapov wrote: >> This nice cache needs to be outside apf to reduce complexity for >> reviewers and since it is useful for others. >> >> Would be good to have memslot-cached kvm_put_guest() and kvm_get_guest(). > Will look into it. In the meantime, you can just drop the caching. >>> + struct kvm_arch_async_pf *arch) >>> +{ >>> + struct kvm_async_pf *work; >>> + >>> + if (vcpu->async_pf_queued>= ASYNC_PF_PER_VCPU) >>> + return 0; >> 100 == too high. At 16 vcpus, this allows 1600 kernel threads to >> wait for I/O. > Number of kernel threads are limited by other means. Slow work subsystem > has its own knobs to tune that. Here we limit how much slow work items > can be queued per vcpu. OK. >> Would have been best if we could ask for a page to be paged in >> asynchronously. >> > You mean to have core kernel facility for that? I agree it would be > nice, but much harder. Yes, that's what I meant. -- error compiling committee.c: too many arguments to function -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org