Anthony Liguori wrote: > Hi Ryo, > > Ryo Tsuruta wrote: > >> Hello all, >> >> I've implemented a block device which throttles block I/O bandwidth, >> which I called dm-ioband, and been trying to throttle I/O bandwidth on >> KVM environment. But unfortunately it doesn't work well, the number of >> issued I/Os is not according to the bandwidth setting. >> On the other hand, I got the good result when accessing directly to >> the local disk on the local machine. >> >> I'm not so familiar with KVM. Could anyone give me any advice? >> > > If you are using virtio drivers in the guest (which I presume you are > given the reference to /dev/vda), try using the following -drive syntax: > > -drive file=/dev/mapper/ioband1,if=virtio,boot=on,cache=off > > This will force the use of O_DIRECT. By default, QEMU does not open > with O_DIRECT so you'll see page cache effects. > >
Good point. But IIRC cache=off is not limited to virtio? -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
