But I am able to set static limits in the config for rbd :) All I want is a change on-the-fly. It is NOT cgroups mechanism, but completely qemu-driven. On Tue, Apr 3, 2012 at 12:21 PM, Wido den Hollander <wido@xxxxxxxxx> wrote: > Hi, > > Op 3-4-2012 10:02, Andrey Korolyov schreef: > >> Hi, >> >> # virsh blkdeviotune Test vdb --write_iops_sec 50 //file block device >> >> # virsh blkdeviotune Test vda --write_iops_sec 50 //rbd block device >> error: Unable to change block I/O throttle >> error: invalid argument: No device found for specified path > > > That is correct. As far as I know iotune uses the underlying cgroups from > the OS. > > RBD devices (when using Qemu) are not block devices which can be managed by > cgroups. That's why it's not working and you get the error that the device > can't be found. > > There is however somebody working on DiskIoThrottling inside Qemu: > http://wiki.qemu.org/Features/DiskIOLimits > > That would work with RBD (he even names Ceph :) ) > > Wido > >> >> 2012-04-03 07:38:49.170+0000: 30171: debug : >> virDomainSetBlockIoTune:18317 : dom=0x1114590, (VM: name=Test, >> uuid=8c27bf32-82dc-315a-d0ba-4653b1b3d595), disk=vda, >> params=0x1114600, nparams=1, flags=0 >> 2012-04-03 07:38:49.170+0000: 30169: debug : >> virEventPollMakePollFDs:383 : Prepare n=8 w=11, f=16 e=1 d=0 >> 2012-04-03 07:38:49.170+0000: 30169: debug : >> virEventPollCalculateTimeout:325 : Calculate expiry of 4 timers >> 2012-04-03 07:38:49.170+0000: 30169: debug : >> virEventPollCalculateTimeout:331 : Got a timeout scheduled for >> 1333438734170 >> 2012-04-03 07:38:49.170+0000: 30171: error : qemuDiskPathToAlias:11338 >> : invalid argument: No device found for specified path >> 2012-04-03 07:38:49.170+0000: 30171: debug : virDomainFree:2313 : >> dom=0x1114590, (VM: name=Test, >> uuid=8c27bf32-82dc-315a-d0ba-4653b1b3d595) >> 2012-04-03 07:38:49.170+0000: 30171: debug : virUnrefDomain:276 : >> unref domain 0x1114590 Test 1 >> 2012-04-03 07:38:49.170+0000: 30171: debug : virReleaseDomain:238 : >> release domain 0x1114590 Test 8c27bf32-82dc-315a-d0ba-4653b1b3d595 >> 2012-04-03 07:38:49.170+0000: 30169: debug : >> virEventPollCalculateTimeout:351 : Timeout at 1333438734170 due in >> 5000 ms >> 2012-04-03 07:38:49.170+0000: 30169: debug : virEventPollRunOnce:619 : >> EVENT_POLL_RUN: nhandles=9 imeout=5000 >> 2012-04-03 07:38:49.170+0000: 30171: debug : virReleaseDomain:246 : >> unref connection 0x1177b10 2 >> >> libvir 0.9.10, json-escape patch applied, but seems that this problem >> related to another incorrect path handle. >> >> I`m in doubt if it belongs to libvirt ml or here. >> -- >> 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
