[libvirt] [PATCH v3 10/10] Allow balloon driver collection to be adjusted dynamically
John Ferlan
jferlan at redhat.com
Thu Jul 11 23:56:00 UTC 2013
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")
+ },
+ {.name = "config",
+ .type = VSH_OT_BOOL,
+ .help = N_("affect next boot")
+ },
+ {.name = "live",
+ .type = VSH_OT_BOOL,
+ .help = N_("affect running domain")
+ },
+ {.name = "current",
+ .type = VSH_OT_BOOL,
+ .help = N_("affect current domain")
+ },
{.name = NULL}
};
@@ -325,15 +342,56 @@ cmdDomMemStat(vshControl *ctl, const vshCmd *cmd)
struct _virDomainMemoryStat stats[VIR_DOMAIN_MEMORY_STAT_NR];
unsigned int nr_stats;
size_t i;
+ int ret = false;
+ int rv = 0;
+ int period = -1;
+ bool config = vshCommandOptBool(cmd, "config");
+ bool live = vshCommandOptBool(cmd, "live");
+ bool current = vshCommandOptBool(cmd, "current");
+ unsigned int flags = VIR_DOMAIN_AFFECT_CURRENT;
+
+ VSH_EXCLUSIVE_OPTIONS_VAR(current, live);
+ VSH_EXCLUSIVE_OPTIONS_VAR(current, config);
+ if (config)
+ flags |= VIR_DOMAIN_AFFECT_CONFIG;
+ if (live)
+ flags |= VIR_DOMAIN_AFFECT_LIVE;
if (!(dom = vshCommandOptDomain(ctl, cmd, &name)))
return false;
+ /* If none of the options were specified and we're active
+ * then be sure to allow active modification */
+ if (!current && !live && !config && virDomainIsActive(dom) == 1)
+ flags |= VIR_DOMAIN_AFFECT_LIVE;
+
+ /* Providing a period will adjust the balloon driver collection period.
+ * This is not really an unsigned long, but it
+ */
+ if ((rv = vshCommandOptInt(cmd, "period", &period)) < 0) {
+ vshError(ctl, "%s",
+ _("Unable to parse integer parameter."));
+ goto cleanup;
+ }
+ if (rv > 0) {
+ if (period < 0) {
+ vshError(ctl, _("Invalid collection period value '%d'"), period);
+ goto cleanup;
+ }
+
+ if (virDomainSetMemoryStatsPeriod(dom, period, flags) < 0) {
+ vshError(ctl, "%s",
+ _("Unable to change balloon collection period."));
+ } else {
+ ret = true;
+ }
+ goto cleanup;
+ }
+
nr_stats = virDomainMemoryStats(dom, stats, VIR_DOMAIN_MEMORY_STAT_NR, 0);
if (nr_stats == -1) {
vshError(ctl, _("Failed to get memory statistics for domain %s"), name);
- virDomainFree(dom);
- return false;
+ goto cleanup;
}
for (i = 0; i < nr_stats; i++) {
@@ -355,8 +413,10 @@ cmdDomMemStat(vshControl *ctl, const vshCmd *cmd)
vshPrint(ctl, "rss %llu\n", stats[i].val);
}
+ ret = true;
+cleanup:
virDomainFree(dom);
- return true;
+ return ret;
}
/*
diff --git a/tools/virsh.pod b/tools/virsh.pod
index 94fe897..729a6e3 100644
--- a/tools/virsh.pod
+++ b/tools/virsh.pod
@@ -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
--
1.8.1.4
More information about the libvir-list
mailing list