Bug 559762

Summary:	QEMU driver nodeinfo is wrong when using cpufreq scaling
Product:	[Community] Virtualization Tools	Reporter:	Thomas Treutner <thomas>
Component:	libvirt	Assignee:	Libvirt Maintainers <libvirt-maint>
Status:	CLOSED WONTFIX	QA Contact:
Severity:	medium	Docs Contact:
Priority:	low
Version:	unspecified	CC:	berrange, crobinso, thomas, xen-maint
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Hardware:	All
OS:	Linux
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Fixed In Version:		Doc Type:	Bug Fix
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Clone Of:		Environment:
Last Closed:	2016-03-20 23:37:25 UTC	Type:	---
Regression:	---	Mount Type:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Thomas Treutner 2010-01-28 22:05:24 UTC

Description of problem:
When using cpufreq kernel module with e.g. ondemand governor, libvirt nodeinfo gets cpu frequency wrong as it just reads /proc/cpuinfo

Version-Release number of selected component (if applicable):
latest git

How reproducible:


Steps to Reproduce:
1. modprobe cpufreq_ondemand
2. virsh -c qemu:///system nodeinfo

  
Actual results:
e.g. 800 MHz, as in /sys/devices/system/cpu/cpuN/cpufreq/cpuinfo_cur_freq

Expected results:
e.g. 3200 MHz, as in /sys/devices/system/cpu/cpuN/cpufreq/scaling_max_freq

Additional info:
I think it would make sense to consider the case where someone might set different max frequencies for different cores. I think i7 supports it? Problem is, data structures would get more complicated, as frequency would have to be stored per core.

/sys/devices/system/cpu/cpuN/cpufreq/cpuinfo_max_freq should IMHO not be considered, as it doesn't consider the current scaling governor.

Comment 1 Cole Robinson 2016-03-20 23:37:25 UTC

Sorry this never received a response. We get the CPU speed from /proc/cpuinfo... it's really just a bit of info about the host and not meant to be an accurate representation of what the host is currently running at. Closing as WONTFIX