>>Once librbd/librados can eliminate all the >>threading/queuing slowdowns, a similar approach could be extended to >>RBD images without the need to open multiple copies of the same image. Thanks Jason, that's a really good news ! ----- Mail original ----- De: "Jason Dillaman" <jdillama@xxxxxxxxxx> À: "aderumier" <aderumier@xxxxxxxxx> Cc: "Somnath Roy" <Somnath.Roy@xxxxxxxxxxx>, "Samuel Just" <sjust@xxxxxxxxxx>, "ceph-devel" <ceph-devel@xxxxxxxxxxxxxxx> Envoyé: Mardi 31 Mai 2016 21:57:29 Objet: Re: Severe performance degradation with jewel rbd image That QEMU patch looks like it only supports raw devices and pre-allocated files. Once librbd/librados can eliminate all the threading/queuing slowdowns, a similar approach could be extended to RBD images without the need to open multiple copies of the same image. On Sat, May 28, 2016 at 3:29 AM, Alexandre DERUMIER <aderumier@xxxxxxxxx> wrote: > Hi, > > qemu should have soon multithreaded disk access support (multi queues + multi iothreads) > > https://lists.gnu.org/archive/html/qemu-devel/2016-05/msg05023.html > > Do you think it'll work with exclusive-lock ? > > ----- Mail original ----- > De: "Jason Dillaman" <jdillama@xxxxxxxxxx> > À: "Somnath Roy" <Somnath.Roy@xxxxxxxxxxx> > Cc: "Samuel Just" <sjust@xxxxxxxxxx>, "ceph-devel" <ceph-devel@xxxxxxxxxxxxxxx> > Envoyé: Jeudi 26 Mai 2016 20:52:26 > Objet: Re: Severe performance degradation with jewel rbd image > > You can dynamically enable/disable exclusive-lock, object-map, > fast-diff, and journaling after the image is created via "rbd feature > disable <image-spec> <feature>". The deep-flatten feature can be > disabled-only via the same CLI. > -- > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Jason -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
