Bug 601690

Summary:	virtio balloon driver does not include extended memory statistics
Product:	Red Hat Enterprise Linux 6	Reporter:	Daniel Berrangé <berrange>
Component:	kernel	Assignee:	Amit Shah <amit.shah>
Status:	CLOSED CURRENTRELEASE	QA Contact:	Virtualization Bugs <virt-bugs>
Severity:	medium	Docs Contact:
Priority:	low
Version:	6.0	CC:	amit.shah, juzhang, lihuang, tburke, virt-maint
Target Milestone:	rc
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:
Clones:	601692 802680 (view as bug list)		Environment:
Last Closed:	2010-11-11 16:10:12 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:
Bug Blocks:	802680

Description Daniel Berrangé 2010-06-08 13:29:22 UTC

Description of problem:
KVM and libvirt in RHEL6 have support for querying extended memory statistics from the guest kernel balloon driver. The RHEL6 kernel, however, is missing this since IIRC it was only added in 2.6.34. This is causing frequent bug reports from beta testers expecting extended statistics to be present in RHEL6 and is also useful information for host admins. The code is well isolated from the rest of the kernel, so it should be feasible to backport this.


Version-Release number of selected component (if applicable):
kernel-2.6.32-33.el6
libvirt-0.8.1-7.el6.x86_64
qemu-kvm-0.12.1.2-2.50.el6.x86_64

How reproducible:
Always

Steps to Reproduce:
1. Boot a RHEL6 KVM guest
2. Run 'virsh dommemstat $GUESTNAME' on the host
3.
  
Actual results:
No output

Expected results:
Similar output to

# virsh dommemstat f14x86_64
swap_in 0
swap_out 0
major_fault 1421
minor_fault 5607546
unused 26672
available 794344



Additional info:
There appear to be at least 3 upstream patches required to provide this support in the kernel virtio balloon driver.

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=9564e138b1f6eb137f7149772438d3f3fb3277dd
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=1f34c71afe5115e77a49c4e67720a66e27053e54
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=169c246a30808588436794e96a97c61a01af9bed

Comment 2 RHEL Program Management 2010-06-08 13:58:37 UTC

This feature request did not get resolved in time for Feature Freeze
for the current Red Hat Enterprise Linux release and has now been
denied. It has been proposed for the next Red Hat Enterprise Linux
release. If you would still like it considered for the current
release as an exception, please make that request with your support
representative.

Comment 4 RHEL Program Management 2010-06-08 17:53:21 UTC

This request was evaluated by Red Hat Product Management for inclusion in a Red
Hat Enterprise Linux major release.  Product Management has requested further
review of this request by Red Hat Engineering, for potential inclusion in a Red
Hat Enterprise Linux Major release.  This request is not yet committed for
inclusion.

Comment 5 Aristeu Rozanski 2010-07-01 16:21:39 UTC

Patch(es) available on kernel-2.6.32-42.el6

Comment 8 lihuang 2010-08-01 16:18:30 UTC

verified on kernel-2.6.32-52.el6

1. on guest : 
[root@dhcp-91-115 ~]# free 
             total       used       free     shared    buffers     cached
Mem:        851084     338288     512796          0      78412     105640
-/+ buffers/cache:     154236     696848
Swap:      6258680          0    6258680

2. on host 
virsh # dommemstat 17
swap_in 0
swap_out 0
major_fault 781
minor_fault 1815889
unused 512812
available 851084

3. on host 
virsh # setmem 17 4096000

4. on host 
virsh # dommemstat 17
swap_in 0
swap_out 0
major_fault 781
minor_fault 1827031
unused 3584788
available 3923084

5. on guest 
[root@dhcp-91-115 ~]# free 
             total       used       free     shared    buffers     cached
Mem:       3923084     338304    3584780          0      78412     105640
-/+ buffers/cache:     154252    3768832
Swap:      6258680          0    6258680

Comment 9 releng-rhel@redhat.com 2010-11-11 16:10:12 UTC

Red Hat Enterprise Linux 6.0 is now available and should resolve
the problem described in this bug report. This report is therefore being closed
with a resolution of CURRENTRELEASE. You may reopen this bug report if the
solution does not work for you.