On Thu, Sep 7, 2017 at 4:05 PM, Sahid Orentino Ferdjaoui < sferd...@redhat.com> wrote:
> On Wed, Sep 06, 2017 at 11:57:25PM -0400, Jay Pipes wrote: > > Sahid, Stephen, what are your thoughts on this? > > > > On 09/06/2017 10:17 PM, Yaguang Tang wrote: > > > I think the fact that RamFilter can't deal with huge pages is a bug , > > > duo to this limit, we have to set a balance between normal memory and > > > huge pages to use RamFilter and NUMATopologyFilter. what do you think > > > Jay? > > Huge Pages has been built on top of the NUMA Topology > implementation. You have to consider isolate all hosts which are going > to handle NUMA instances to a specific host aggregate. > > We don't want RAMFilter to handle any NUMA related feature (in Nova > world: hugepages, pinning, realtime...) but we don't want it blocking > scheduling and that should not be the case. > > I'm surprised to see this bug I think libvirt is reporting the total > amount of physical RAM available on the host and that is not depending > of the size of the pages. > > So If that is true libvirt is reporting only the amount of small pages > memory available we will probably have to fix that point instead of > the RAMFilter. > If we fix it this way, the issue still exists, as long as user use RamFilter and NUMATopologyFilter toghther. Libvirt reports total memory which contains huge pages but normal instance can't use. > > That because we don't want to add "hack" on all filters to just pass > when instances provide NUMA Topology constraints and we can't > configure the scheduler to use specific filters per aggregate. > How about fixing RamFilter to just pass if the instance extra specs specifies huge pages ? > > s. > > > > > > > On Wed, Sep 6, 2017 at 9:22 PM, Jay Pipes <jaypi...@gmail.com > > > <mailto:jaypi...@gmail.com>> wrote: > > > > > > On 09/06/2017 01:21 AM, Weichih Lu wrote: > > > > > > Thanks for your response. > > > > > > Is this mean if I want to create an instance with flavor: 16G > > > memory (hw:mem_page_size=large), I need to preserve memory more > > > than 16GB ? > > > This instance consume hugepages resource. > > > > > > > > > You need to reserve fewer 1GB huge pages than 50 if you want to > > > launch a 16GB instance on a host with 64GB of RAM. Try reserving 32 > > > 1GB huge pages. > > > > > > Best, > > > -jay > > > > > > 2017-09-06 1:47 GMT+08:00 Jay Pipes <jaypi...@gmail.com > > > <mailto:jaypi...@gmail.com> <mailto:jaypi...@gmail.com > > > <mailto:jaypi...@gmail.com>>>: > > > > > > > > > Please remember to add a topic [nova] marker to your > > > subject line. > > > Answer below. > > > > > > On 09/05/2017 04:45 AM, Weichih Lu wrote: > > > > > > Dear all, > > > > > > I have a compute node with 64GB ram. And I set 50 > > > hugepages wiht > > > 1GB hugepage size. I used command "free", it shows > free > > > memory > > > is about 12GB. And free hugepages is 50. > > > > > > > > > Correct. By assigning hugepages, you use the memory > > > allocated to the > > > hugepages. > > > > > > Then I launch an instance with 16GB memory, set flavor > > > tag : > > > hw:mem_page_size=large. It show Error: No valid host > > > was found. > > > There are not enough hosts available. > > > > > > > > > Right, because you have only 12G of RAM available after > > > creating/allocating 50G out of your 64G. > > > > > > Huge pages are entirely separate from the normal memory > that a > > > flavor consumes. The 16GB memory in your flavor is RAM > > > consumed on > > > the host. The huge pages are individual things that are > > > consumed by > > > the NUMA topology that your instance will take. RAM != > huge > > > pages. > > > Totally different things. > > > > > > And I check nova-scheduler log. My > > > > > > compute is removed by RamFilter. I can launch an > > > instance with > > > 8GB memory successfully, or I can launch an instance > > > with 16GB > > > memory sucessfully by remove RamFilter. > > > > > > > > > That's because RamFilter doesn't deal with huge pages. > > > Because huge > > > pages are a different resource than memory. The page > itself > > > is the > > > resource. > > > > > > The NUMATopologyFilter is the scheduler filter that > > > evaluates the > > > huge page resources on a compute host and determines if > the > > > there > > > are enough *pages* available for the instance. Note that > I say > > > *pages* because the unit of resource consumption for huge > > > pages is > > > not MB of RAM. It's a single memory page. > > > > > > Please read this excellent article by Steve Gordon for > > > information > > > on what NUMA and huge pages are and how to use them in > Nova: > > > > > > http://redhatstackblog.redhat.com/2015/09/15/driving-in-the- > fast-lane-huge-page-support-in-openstack-compute/ > > > <http://redhatstackblog.redhat.com/2015/09/15/driving- > in-the-fast-lane-huge-page-support-in-openstack-compute/> > > > <http://redhatstackblog.redhat.com/2015/09/15/driving- > in-the-fast-lane-huge-page-support-in-openstack-compute/ > > > <http://redhatstackblog.redhat.com/2015/09/15/driving- > in-the-fast-lane-huge-page-support-in-openstack-compute/>> > > > > > > Best, > > > -jay > > > > > > Does RamFilter only check free memory but not free > > > hugepages? > > > How can I solve this problem? > > > > > > I use openstack mitaka version. > > > > > > thanks > > > > > > WeiChih, Lu. > > > > > > Best Regards. > > > > > > > > > _______________________________________________ > > > Mailing list: > > > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > > <http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > > > > <http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > > <http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > >> > > > Post to : openstack@lists.openstack.org > > > <mailto:openstack@lists.openstack.org> > > > <mailto:openstack@lists.openstack.org > > > <mailto:openstack@lists.openstack.org>> > > > Unsubscribe : > > > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > > <http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > > > > <http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > > <http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > >> > > > > > > > > > _______________________________________________ > > > Mailing list: > > > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > > <http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > > > > <http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > > <http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > >> > > > Post to : openstack@lists.openstack.org > > > <mailto:openstack@lists.openstack.org> > > > <mailto:openstack@lists.openstack.org > > > <mailto:openstack@lists.openstack.org>> > > > Unsubscribe : > > > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > > <http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > > > > <http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > > <http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > >> > > > > > > > > > > > > > > > _______________________________________________ > > > Mailing list: > > > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > > <http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > > > > Post to : openstack@lists.openstack.org > > > <mailto:openstack@lists.openstack.org> > > > Unsubscribe : > > > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > > <http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > > > > > > > > > > _______________________________________________ > > > Mailing list: > > > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > > <http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack> > > > Post to : openstack@lists.openstack.org > > > <mailto:openstack@lists.openstack.org> > > > Unsubscribe : > > > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack > > > <http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack> > > > > > > > > > > > > > > > -- > > > Tang Yaguang > > > > > > > -- Tang Yaguang
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