On Fri, Apr 15, 2011 at 04:43:03PM +0900, KAMEZAWA Hiroyuki wrote:
On Fri, 15 Apr 2011 09:43:15 +0200 Matthias Bolte <matthias.bolte@googlemail.com> wrote:
2011/4/15 KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>:
Per (host) cpu activity of VMs are very insterested numbers when running VMs on large SMPs. virt-top -1 mode tries to provide the information. (But it's not implemented.)
This patch adds a libvirt interface to get per cpu statistics of each nodes. This patch just adds an interface and driver entry points. So, - doesn't include patches for python. - doesn't include any driver.
Following patches will add some drivers and codes for python.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> --- include/libvirt/libvirt.h.in | 13 ++++++++++ src/driver.h | 6 ++++ src/esx/esx_driver.c | 1 + src/libvirt.c | 55 ++++++++++++++++++++++++++++++++++++++++++ src/libvirt_public.syms | 4 +++ src/libxl/libxl_driver.c | 1 + src/lxc/lxc_driver.c | 1 + src/openvz/openvz_driver.c | 1 + src/phyp/phyp_driver.c | 1 + src/qemu/qemu_driver.c | 1 + src/remote/remote_driver.c | 1 + src/test/test_driver.c | 1 + src/uml/uml_driver.c | 1 + src/vbox/vbox_tmpl.c | 1 + src/vmware/vmware_driver.c | 1 + src/xen/xen_driver.c | 1 + src/xenapi/xenapi_driver.c | 1 + 17 files changed, 91 insertions(+), 0 deletions(-)
diff --git a/include/libvirt/libvirt.h.in b/include/libvirt/libvirt.h.in index 5783303..6b9292c 100644 --- a/include/libvirt/libvirt.h.in +++ b/include/libvirt/libvirt.h.in @@ -400,6 +400,13 @@ struct _virDomainMemoryStat {
typedef virDomainMemoryStatStruct *virDomainMemoryStatPtr;
+typedef struct _virDomainPcpuStat virDomainPcpuStatStruct; + +struct _virDomainPcpuStat { + unsigned long long cpuTime; +}; +
NACK to adding another public struct to the API.
Oh, yes. I searched a sutiable existing API but cannot found.
Maybe adding new enum to Usui's work will be good but I need an array. Hmm, returning an array of unsigned long long is ok ?
It's not expendable. As a stylistic nit pleas don't use the term PCPU as this looks like "Physical CPU". Just call it virDomainPerVcpuStat at least.
Ah, no, this is PerPhysicalStat
Also do you really need the absolute CPU time? yes, for virt-top -1.
I don't think that is correct. What virt-top ultimately displays to the end user is a % utilization. So it would be happy to get data in either % util & display that directly, or get absolute CPU time and calculate deltas to display % util. I wonder if we could provide an API that could be used to provide either per-VCPU or per-PCPU statistics in one go, so that we can finally have an API for cpu time that works well for VMWare. eg typedef struct _virDomainCPUTime virDomainCPUTime; typedef virDomainCPUTime *virDomainCPUTimePtr; #define VIR_DOMAIN_CPUTIME_ABS "abs" #define VIR_DOMAIN_CPUTIME_UTIL "util" ...define more stats later if desired... struct _virDomainCPUTime { char field[VIR_DOMAIN_CPU_TIME_FIELD_LENGTH]; unsigned long long value; }; typedef enum { VIR_DOMAIN_CPU_TIME_VIRTUAL = 0, VIR_DOMAIN_CPU_TIME_PHYSICAL = 1, } virDomainCPUTimeFlags; int virDomainGetCPUTime(virDomainPtr dom, virDomainCPUTimePtr stats, int *nstats, unsigned int flags); When querying per-virtual CPU time, nstats would be the number of virtual CPUs in the guest. eg virDomainInfo info; virDomainGetInfo(dom, &info); virDomainCPUTimePtr stats; stats = malloc(sizeof(*stats)*info.nrVirtCPU); virDomainGetCPUTime(dom, stats, info.nrVirtCPU, VIR_DOMAIN_CPU_TIME_VIRTUAL); Or to get the break down per physical CPU, use the VIR_NODEINFO_MAX_CPUS macro virNodeInfo info; virNodeGetInfo(conn, &info); virDomainCPUTimePtr stats; stats = malloc(sizeof(*stats)*VIR_NODEINFO_MAX_CPUS(info)) virDomainGetCPUTime(dom, stats, VIR_NODEINFO_MAX_CPUS(info), VIR_DOMAIN_CPU_TIME_PHYSICAL); We could also allow 'nstats' to be 0, in which case the API would simply populate 'nstats' with the required number and return. The caller can then re-invoke with correct nstats and allocated memory. 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 :|