From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2435FC433DF for ; Tue, 26 May 2020 11:38:56 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id DBD682084C for ; Tue, 26 May 2020 11:38:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="1N6YuY0h" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DBD682084C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 7CD40800A4; Tue, 26 May 2020 07:38:55 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 77D0780061; Tue, 26 May 2020 07:38:55 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 692C5800A4; Tue, 26 May 2020 07:38:55 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0199.hostedemail.com [216.40.44.199]) by kanga.kvack.org (Postfix) with ESMTP id 4DA6E80061 for ; Tue, 26 May 2020 07:38:55 -0400 (EDT) Received: from smtpin01.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id EEF622491 for ; Tue, 26 May 2020 11:38:54 +0000 (UTC) X-FDA: 76858673388.01.stone28_139713f54df15 X-HE-Tag: stone28_139713f54df15 X-Filterd-Recvd-Size: 3001 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf03.hostedemail.com (Postfix) with ESMTP for ; Tue, 26 May 2020 11:38:54 +0000 (UTC) Received: from kernel.org (unknown [87.70.212.59]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C32A1207CB; Tue, 26 May 2020 11:38:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590493133; bh=Wajw1ceENB9jmRhxQhR29w1N42Not5ApNmO0wbs23pY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=1N6YuY0hI/08pJzS1NvVuzOOBihDQpySVba0Krk295SyXzDWHiffI26uav4ppjIbs wQGF3JptzzAzWlYbkIxctDjMjC9vTc8hSrONfenzVWnDWmDunT42Q++sXWRJSEm7wM Dj6Y3E0YTUqm2BpIau0CmHykWgCcHsYOQy/5HTz4= Date: Tue, 26 May 2020 14:38:44 +0300 From: Mike Rapoport To: Liran Alon Cc: "Kirill A. Shutemov" , Dave Hansen , Andy Lutomirski , Peter Zijlstra , Paolo Bonzini , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , David Rientjes , Andrea Arcangeli , Kees Cook , Will Drewry , "Edgecombe, Rick P" , "Kleen, Andi" , x86@kernel.org, kvm@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" Subject: Re: [RFC 00/16] KVM protected memory extension Message-ID: <20200526113844.GC48741@kernel.org> References: <20200522125214.31348-1-kirill.shutemov@linux.intel.com> <42685c32-a7a9-b971-0cf4-e8af8d9a40c6@oracle.com> <20200526061721.GB48741@kernel.org> <8866ff79-e8fd-685d-9a1d-72acff5bf6bb@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8866ff79-e8fd-685d-9a1d-72acff5bf6bb@oracle.com> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, May 26, 2020 at 01:16:14PM +0300, Liran Alon wrote: > > On 26/05/2020 9:17, Mike Rapoport wrote: > > On Mon, May 25, 2020 at 04:47:18PM +0300, Liran Alon wrote: > > > On 22/05/2020 15:51, Kirill A. Shutemov wrote: > > > > > Out of curiosity, do we actually have some numbers for the "non-trivial > > performance cost"? For instance for KVM usecase? > > > Dig into XPFO mailing-list discussions to find out... > I just remember that this was one of the main concerns regarding XPFO. The XPFO benchmarks measure total XPFO cost, and huge share of it comes from TLB shootdowns. It's not exactly measurement of the imapct of the direct map fragmentation to workload running inside a vitrual machine. > -Liran -- Sincerely yours, Mike.