From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44949) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1as5g2-0005hJ-GF for qemu-devel@nongnu.org; Mon, 18 Apr 2016 05:41:07 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1as5fy-0002eg-Mg for qemu-devel@nongnu.org; Mon, 18 Apr 2016 05:41:06 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47580) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1as5fy-0002eT-H1 for qemu-devel@nongnu.org; Mon, 18 Apr 2016 05:41:02 -0400 Date: Mon, 18 Apr 2016 10:40:57 +0100 From: "Dr. David Alan Gilbert" Message-ID: <20160418094056.GB2222@work-vm> References: <20160413080545.GA2270@work-vm> <20160413114103.GB2270@work-vm> <20160413125053.GC2270@work-vm> <20160413205132.GG26364@redhat.com> <20160414123441.GF2252@work-vm> <20160414162230.GC9976@redhat.com> <20160415125236.GA3376@node.shutemov.name> <20160415134233.GG2229@work-vm> <20160415152330.GB3376@node.shutemov.name> <20160415221943.GJ9976@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160415221943.GJ9976@redhat.com> Subject: Re: [Qemu-devel] post-copy is broken? List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Andrea Arcangeli Cc: "Kirill A. Shutemov" , kirill.shutemov@linux.intel.com, "Li, Liang Z" , Amit Shah , "qemu-devel@nongnu.org" , "quintela@redhat.com" , linux-mm@kvack.org * Andrea Arcangeli (aarcange@redhat.com) wrote: > On Fri, Apr 15, 2016 at 06:23:30PM +0300, Kirill A. Shutemov wrote: > > The same here. Freshly booted machine with 64GiB ram. I've checked > > /proc/vmstat: huge pages were allocated > > I tried the test in a loop and I can't reproduce it here. > > Tested with gcc 4.9.3 and glibc 2.21 and glibc 2.22 so far, > qemu&kernel/KVM latest upstream (4.6-rc3..). > > You can run this in between each invocation to guarantee all memory is > backed by THP (no need of reboot): > > # echo 3 >/proc/sys/vm/drop_caches > # echo >/proc/sys/vm/compact_memory > > 4.5 kernel built with gcc 5.3.1 run on a older userland worked fine > too. > > Next thing to test would be if there's something wrong with qemu built > with gcc 5.3.1 if run on top of a 4.4 kernel? It's also working for me on f24 (4.5.0-320 packaged kernel) on a real machine; so we currently have two sets that break: a) Liang Li's setup (that breaks with the migrate of a real VM but I don't think we have any details of the setup); works with 4.4.x breaks with 4.5.x b) f24 nested with my test, with THP enabled after Kirill's changes. Dave -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK