[libvirt] [PATCH 1/2] docs: virsh: Add minimal documentation for 'mbmt' and 'mbml' perf events

[John Ferlan]

On 06/17/2016 04:25 AM, Peter Krempa wrote:
> ---
>  tools/virsh.pod | 11 ++++++++---
>  1 file changed, 8 insertions(+), 3 deletions(-)
> 
> diff --git a/tools/virsh.pod b/tools/virsh.pod
> index 1e56660..b11e4c3 100644
> --- a/tools/virsh.pod
> +++ b/tools/virsh.pod
> @@ -901,6 +901,8 @@ I<--interface> returns:
> 
>  I<--perf> returns the statistics of all enabled perf events:
>  "perf.cache" - the cache usage in Byte currently used

^^^
cmt?

Like a gift that keeps on giving... Adjust it now or trivially in a pre
or follow up patch.

> +"perf.mbmt" - total system bandwidth from one level of cache
> +"perf.mbml" - bandwidth of memory traffic for a memory controller
> 
>  I<--block> returns information about disks associated with each
>  domain.  Using the I<--backing> flag extends this information to
> @@ -2180,9 +2182,12 @@ from different sources can be supported by perf.
>  Currently only QEMU/KVM supports this command. The I<--enable> and I<--disable>
>  option combined with B<eventSpec> can be used to enabled or disable specific
>  performance event. B<eventSpec> is a string list of one or more events
> -separated by commas. However, just "cmt" event is supported presently. CMT is a
> -PQos (Platform Qos) feature to monitor the usage of cache by applications
> -running on the platform.
> +separated by commas. Valid event names are "cmt", "mbmt", "mbml".
> +CMT is a PQos (Platform Qos) feature to monitor the usage of cache by
> +applications running on the platform.

MBM (Memory Bandwidth Mpnitoring) provides a way to monitor the Total
system memory bandwidth between one level of cache and another (mbmt)
and the amount of data (bytes/s) sent through the memory controller on
the socket (mbml).


ACK  w/ this (text paraphrased from commit id '90b9995d1' before I
completed my first cup of coffee)

John
> +
> +The statistics can be retrieved using the B<domstats> command using the
> +I<--perf> flag.
> 
>  If I<--live> is specified, affect a running guest.
>  If I<--config> is specified, affect the next boot of a persistent guest.
>