Re: [libvirt] [PATCH v3 10/10] Allow balloon driver collection to be adjusted dynamically

Use the virDomainSetMemoryStatsPeriodFlags() to pass a period defined by usage of a new --period option in order to set the collection period for the balloon driver. This may enable or disable the collection based on the value. Add the --current, --live, & --config options to dommemstat. --- docs/formatdomain.html.in | 11 +++++++- tools/virsh-domain-monitor.c | 66 ++++++++++++++++++++++++++++++++++++++++++-- tools/virsh.pod | 22 ++++++++++++++- 3 files changed, 94 insertions(+), 5 deletions(-) diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in index 93d2416..df84ed2 100644 --- a/docs/formatdomain.html.in +++ b/docs/formatdomain.html.in @@ -4660,7 +4660,16 @@ qemu-kvm -net nic,model=? /dev/null <p> The optional <code>period</code> allows the QEMU virtio memory balloon driver to provide statistics through the <code>virsh - dommemstat [domain]</code> command. + dommemstat [domain]</code> command. By default, collection is + not enabled. In order to enable, use the <code>virsh dommemstat + [domain] --period [number]</code> command or <code>virsh edit</code> + command to add the option to the XML definition. + The <code>virsh dommemstat</code> will accept the options + <code>--live</code>, <code>--current</code>, or <code>--config</code>. + If an option is not provided, the change for a running domain will + only be made to the active guest. + If the QEMU driver is not at the right + revision, the attempt to set the period will fail. <span class='since'>Since 1.1.1, requires QEMU 1.5</span> </p> </dd> diff --git a/tools/virsh-domain-monitor.c b/tools/virsh-domain-monitor.c index 5fbd32c..4cbf105 100644 --- a/tools/virsh-domain-monitor.c +++ b/tools/virsh-domain-monitor.c @@ -314,6 +314,23 @@ static const vshCmdOptDef opts_dommemstat[] = { .flags = VSH_OFLAG_REQ, .help = N_("domain name, id or uuid") }, + {.name = "period", + .type = VSH_OT_DATA, + .flags = VSH_OFLAG_EMPTY_OK, + .help = N_("period in seconds to set collection") + },

@@ -668,10 +668,30 @@ Both I<--live> and I<--current> flags may be given, but I<--current> is exclusive. If no flag is specified, behavior is different depending on hypervisor. -=item B<dommemstat> I<domain> +=item B<dommemstat> I<domain> [I<period> B<seconds>] +[[I<--config>] [I<--live>] | [I<--current>]] Get memory stats for a running domain. +Depending on the hypervisor a variety of statistics can be returned + +For QEMU/KVM with a memory balloon, setting the optional I<period> to a +value larger than 0 in seconds will allow the balloon driver to return +additional statistics which will be displayed by subsequent B<dommemstat> +commands. Setting the I<period> to 0 will stop the balloon driver collection, +but does not clear the statistics in the balloon driver. Requires at least +QEMU/KVM 1.5 to be running on the host. + +The I<--live>, I<--config>, and I<--current> flags are only valid when using +the I<period> option in order to set the collection period for the balloon +driver. If I<--live> is specified, only the running guest collection period +is affected. If I<--config> is specified, affect the next boot of a persistent +guest. If I<--current> is specified, affect the current guest state. + +Both I<--live> and I<--config> flags may be given, but I<--current> is +exclusive. If no flag is specified, behavior is different depending +on the guest state. + =item B<domblkerror> I<domain> Show errors on block devices. This command usually comes handy when