[libvirt] [RFC PATCH v2 1/3] qemu: Expose additional timing metrics for 'setup' and 'mbps'

Daniel P. Berrange berrange at redhat.com
Mon Feb 3 12:52:26 UTC 2014


On Mon, Feb 03, 2014 at 01:32:59PM +0100, Jiri Denemark wrote:
> On Mon, Jan 13, 2014 at 14:28:10 +0800, mrhines at linux.vnet.ibm.com wrote:
> > From: "Michael R. Hines" <mrhines at us.ibm.com>
> > 
> > RDMA migration uses the 'setup' state in QEMU to optionally lock
> > all memory before the migration starts. The total time spent in
> > this state is already exposed by QEMU, so expose it in libvirt.
> > 
> > Additionally, QEMU also now exports migration throughput (mbps),
> > so let's see that one too...
> > 
> > Signed-off-by: Michael R. Hines <mrhines at us.ibm.com>
> > ---
> >  include/libvirt/libvirt.h.in | 15 +++++++++++++++
> >  src/qemu/qemu_driver.c       | 14 ++++++++++++++
> >  src/qemu/qemu_monitor.h      | 12 ++++++++++++
> >  src/qemu/qemu_monitor_json.c |  8 ++++++++
> >  4 files changed, 49 insertions(+)
> > 
> > diff --git a/include/libvirt/libvirt.h.in b/include/libvirt/libvirt.h.in
> > index 5aad75c..5ac2694 100644
> > --- a/include/libvirt/libvirt.h.in
> > +++ b/include/libvirt/libvirt.h.in
> > @@ -4153,6 +4153,21 @@ int virDomainAbortJob(virDomainPtr dom);
> >  #define VIR_DOMAIN_JOB_DOWNTIME                 "downtime"
> >  
> >  /**
> > + * VIR_DOMAIN_JOB_MBPS:
> > + *
> > + * virDomainGetJobStats field: network throughput used while migrating.
> > + */
> > +#define VIR_DOMAIN_JOB_MBPS "mbps"
> 
> I think this would be better as
> 
>     #define VIR_DOMAIN_JOB_THROUGHPUT "throughput"
> 
> And you need to explicitly mention the type of the value returned in
> this parameter.

Hmm, in block I/O tuning XML/APIs we use either

 VIR_DOMAIN_BLOCK_IOTUNE_TOTAL_BYTES_SEC

or

  VIR_DOMAIN_BLKIO_DEVICE_READ_BPS

which would suggest that first we should measure this in bps too,
not mbp, and using either BPS or BYTES_SEC as a constant suffix
is reasonable for consistency.

Daniel
-- 
|: http://berrange.com      -o-    http://www.flickr.com/photos/dberrange/ :|
|: http://libvirt.org              -o-             http://virt-manager.org :|
|: http://autobuild.org       -o-         http://search.cpan.org/~danberr/ :|
|: http://entangle-photo.org       -o-       http://live.gnome.org/gtk-vnc :|




More information about the libvir-list mailing list