From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [RFC 00/10] KVM: Add TMEM host/guest support Date: Mon, 11 Jun 2012 14:17:26 +0300 Message-ID: <4FD5D3C6.6090003@redhat.com> References: <1338988073-6913-1-git-send-email-levinsasha928@gmail.com> <4FCF5A08.7080306@redhat.com> <1339161641.3200.15.camel@lappy> <2c1ba6f0-0089-4bfc-be25-61b55a2c1fbc@default> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Sasha Levin , mtosatti@redhat.com, gregkh@linuxfoundation.org, sjenning@linux.vnet.ibm.com, Konrad Wilk , kvm@vger.kernel.org To: Dan Magenheimer Return-path: Received: from mx1.redhat.com ([209.132.183.28]:23289 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753897Ab2FKLRn (ORCPT ); Mon, 11 Jun 2012 07:17:43 -0400 In-Reply-To: <2c1ba6f0-0089-4bfc-be25-61b55a2c1fbc@default> Sender: kvm-owner@vger.kernel.org List-ID: On 06/08/2012 07:06 PM, Dan Magenheimer wrote: >> From: Avi Kivity [mailto:avi@redhat.com] >> >> These results give about 47 usec per page system time (seems quite >> high), whereas the difference is 0.7 user per page (seems quite low, for >> 1 or 2 syscalls per page). Can you post a snapshot of kvm_stat while >> this is running? > > Note that the userspace difference is likely all noise. > No tmem/zcache activites should be done in userspace. All > the activites result from either a page fault or kswapd. s/user/usec/... > Since each streamed page (assuming no WasActive patch) should > result in one hypercall and one lz01x page compression, I suspect > that 47usec is a good estimate of the sum of those on Sasha's machine. It's a huge number for a page. The newer results give lower numbers, but still quite high. -- error compiling committee.c: too many arguments to function