Re: [Qemu-devel] [libvirt] The design choice for how to enable block I/O throttling function in libvirt

[shu ming]

Zhi Yong Wu:
> On Tue, Aug 30, 2011 at 3:18 PM, shu ming<address@hidden>  wrote:
> > See commens below.
> > Zhi Yong Wu:
> > > HI, folks,
> > >
> > > I am trying to enable block I/O throttling function in libvirt. But
> > > currently i met some design questions, and don't make sure if we
> > > should extend blkiotune to support block I/O throttling or introduce
> > > one new libvirt command "blkiothrottle" to cover it or not. If you
> > > have some better idea, pls don't hesitate to drop your comments.
> > >
> > > If one new libvirt command "blkiothrottle" is introduced, I plan to
> > > design its usage syntax as below:
> > >
> > > virsh # help blkiothrottle
> > >    NAME
> > >      blkiothrottle - Set or display a block disk I/O throttle setting.
> > >
> > >    SYNOPSIS
> > >      blkiothrottle<domain>    <device>    [--bps<number>] [--bps_rd
> > > <number>] [--bps_wr<number>] [--iops<number>] [--iops_rd<number>]
> > > [--iops_wr<number>]
> > >
> > >    DESCRIPTION
> > >      Set or display a block disk I/O throttle setting.
> > >
> > >    OPTIONS
> > >      [--domain]<string>     domain name, id or uuid
> > >      [--device]<string>     block device
> > >      --bps<number>      total throughput limits in bytes/s
> > >      --bps_rd<number>     read throughput limits in bytes/s
> > >      --bps_wr<number>     write throughput limits in bytes/s
> > >      --iops<number>     total operation limits in numbers/s
> > >      --iops_rd<number>     read operation limits in numbers/s
> > >      --iops_wr<number>     write operation limits in numbers/s
> > How to display the current I/O throttle setting of a specific block device
> > here?
> It will show as below:
> virtio0: bps=xxx, bps_rd=xxx, bps_wr=xxx, iops=xxx, iops_rd=xxx, iops_wr=xxx.

With which options to the command?  I guess "blkiothrottle <domain> 
<device>" will display the current setting.