5:12 a.m.
And provide domain summary stat in that case, for lxc backend.
Use case is a container inheriting all devices from the host,
e.g. when doing application containerization.
---
Notes on v2:
- adapted virDomainBlockStats docs
- adapted virsh domblkstat docs
- made virsh actually accept empty disk argument
- pedaling back a bit on the API change - accepting a NULL ptr
for the disk arg would need changing the remote protocol, so
better just take the empty string. Makes this less invasive even.
src/libvirt.c | 8 ++++++--
src/lxc/lxc_driver.c | 10 ++++++++++
tools/virsh-domain-monitor.c | 11 ++++++++---
tools/virsh.pod | 5 +++--
4 files changed, 27 insertions(+), 7 deletions(-)
diff --git a/src/libvirt.c b/src/libvirt.c
index 87a4d46..ead0813 100644
--- a/src/libvirt.c
+++ b/src/libvirt.c
@@ -7781,7 +7781,9 @@ error:
* an unambiguous source name of the block device (the <source
* file='...'/> sub-element, such as "/path/to/image"). Valid
names
* can be found by calling virDomainGetXMLDesc() and inspecting
- * elements within //domain/devices/disk.
+ * elements within //domain/devices/disk. Some drivers might also
+ * accept the empty string for the @disk parameter, and then yield
+ * summary stats for the entire domain.
*
* Domains may have more than one block device. To get stats for
* each you should make multiple calls to this function.
@@ -7847,7 +7849,9 @@ error:
* an unambiguous source name of the block device (the <source
* file='...'/> sub-element, such as "/path/to/image"). Valid
names
* can be found by calling virDomainGetXMLDesc() and inspecting
- * elements within //domain/devices/disk.
+ * elements within //domain/devices/disk. Some drivers might also
+ * accept the empty string for the @disk parameter, and then yield
+ * summary stats for the entire domain.
*
* Domains may have more than one block device. To get stats for
* each you should make multiple calls to this function.
diff --git a/src/lxc/lxc_driver.c b/src/lxc/lxc_driver.c
index bf6fd5c..31f1625 100644
--- a/src/lxc/lxc_driver.c
+++ b/src/lxc/lxc_driver.c
@@ -2046,6 +2046,16 @@ lxcDomainBlockStats(virDomainPtr dom,
goto cleanup;
}
+ if (!*path) {
+ /* empty path - return entire domain blkstats instead */
+ ret = virCgroupGetBlkioIoServiced(priv->cgroup,
+ &stats->rd_bytes,
+ &stats->wr_bytes,
+ &stats->rd_req,
+ &stats->wr_req);
+ goto cleanup;
+ }
+
if ((idx = virDomainDiskIndexByName(vm->def, path, false)) < 0) {
virReportError(VIR_ERR_INVALID_ARG,
_("invalid path: %s"), path);
diff --git a/tools/virsh-domain-monitor.c b/tools/virsh-domain-monitor.c
index b29b82a..6be253f 100644
--- a/tools/virsh-domain-monitor.c
+++ b/tools/virsh-domain-monitor.c
@@ -880,7 +880,7 @@ static const vshCmdOptDef opts_domblkstat[] = {
},
{.name = "device",
.type = VSH_OT_DATA,
- .flags = VSH_OFLAG_REQ,
+ .flags = VSH_OFLAG_EMPTY_OK,
.help = N_("block device")
},
{.name = "human",
@@ -946,8 +946,13 @@ cmdDomblkstat(vshControl *ctl, const vshCmd *cmd)
if (!(dom = vshCommandOptDomain(ctl, cmd, &name)))
return false;
- if (vshCommandOptStringReq(ctl, cmd, "device", &device) < 0)
- goto cleanup;
+ /* device argument is optional now. if it's missing, supply empty
+ string to denote 'all devices'. A NULL device arg would violate
+ API contract.
+ */
+ rc = vshCommandOptStringReq(ctl, cmd, "device", &device); /* and ignore
rc */
+ if (!device)
+ device = "";
rc = virDomainBlockStatsFlags(dom, device, NULL, &nparams, 0);
diff --git a/tools/virsh.pod b/tools/virsh.pod
index 3534b54..c3ca016 100644
--- a/tools/virsh.pod
+++ b/tools/virsh.pod
@@ -616,12 +616,13 @@ If I<--graceful> is specified, don't resort to extreme
measures
(e.g. SIGKILL) when the guest doesn't stop after a reasonable timeout;
return an error instead.
-=item B<domblkstat> I<domain> I<block-device> [I<--human>]
+=item B<domblkstat> I<domain> [I<block-device>] [I<--human>]
Get device block stats for a running domain. A I<block-device> corresponds
to a unique target name (<target dev='name'/>) or source file (<source
file='name'/>) for one of the disk devices attached to I<domain> (see
-also B<domblklist> for listing these names).
+also B<domblklist> for listing these names). On a lxc domain, omitting the
+I<block-device> yields device block stats summarily for the entire domain.
Use I<--human> for a more human readable output.
--
1.8.4