Hi, Am 11.06.2013 um 19:14 schrieb w sun <ws...@hotmail.com>:
> Hi, > > We are currently testing the performance with rbd caching enabled with > write-back mode on our openstack (grizzly) nova nodes. By default, nova fires > up the rbd volumes with "if=none" mode evidenced by the following cmd line > from "ps | grep". > > -drive > file=rbd:ceph-openstack-volumes/volume-949e2e32-20c7-45cf-b41b-46951c78708b:id=ceph-openstack-volumes:key=12347I9RsEoIDBAAi2t+M6+7zMMZoMM+aasiog==:auth_supported=cephx\;none,if=none,id=drive-virtio-disk0,format=raw,serial=949e2e32-20c7-45cf-b41b-46951c78708b,cache=writeback > > > Does anyone know if this should be set to anything else (e.g., if=virtio > suggested by some qemu posts in general)? Given that the underline network > stack for RBD IO is provided by the linux kenerl instead, does this option > bear any relevance for rbd volume performance inside guest VM? there should be something like "-device virtio-blk-pci,drive=drive-virtio-disk0" in reference to the id= for the drive-specification. Furthermore to really check rbd_cache there is s/t like: rbd_cache=true:rbd_cache_size=33554432:rbd_cache_max_dirty=16777216:rbd_cache_target_dirty=8388608 missing in the ":"-list, perhaps after :none:rbd_cache=true:rbd_cache_size=33554432:rbd_cache_max_dirty=16777216:rbd_cache_target_dirty=8388608 cache=writeback is necessary, too. No idea, though, how to teach openstack to use these parameters, sorry. Regards, Oliver. > > Thanks. --weiguo > > > > > _______________________________________________ > ceph-users mailing list > ceph-users@lists.ceph.com > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com _______________________________________________ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
