Bug 795686

Summary:	Disable ShadowFB by default for virtual guests
Product:	Red Hat Enterprise Linux 6	Reporter:	Marko Myllynen <myllynen>
Component:	xorg-x11-drv-vesa	Assignee:	Adam Jackson <ajax>
Status:	CLOSED ERRATA	QA Contact:	Desktop QE <desktop-qa-list>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	6.2	CC:	pcfe, rjones, tpelka
Target Milestone:	rc
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:	xorg-x11-drv-vesa-2.3.2-4.el6	Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2013-02-21 08:04:45 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Bug Depends On:
Bug Blocks:	842499

Description Marko Myllynen 2012-02-21 10:02:59 UTC

Description of problem:
Disabling shadow framebuffer by setting Option "ShadowFB" "Off" in xorg.conf provides a notable performance increase for QEMU/KVM guests using vga display adapter as indicated by glxgears (these numbers are from RHEL 6.2 host/guest on a Lenovo laptop):

ShadowFB On  : 260 FPS
ShadowFB Off : 295 FPS

There's a patch in Fedora already to do this by default:

http://pkgs.fedoraproject.org/gitweb/?p=xorg-x11-drv-vesa.git;a=blob_plain;f=vesa-2.3.0-no-virt-shadowfb.patch;h=4b847dfd402854c2e334c52fff96879ee1f48d33;hb=HEAD

Version-Release number of selected component (if applicable):
RHEL 6.2

Comment 2 RHEL Program Management 2012-07-10 08:54:23 UTC

This request was not resolved in time for the current release.
Red Hat invites you to ask your support representative to
propose this request, if still desired, for consideration in
the next release of Red Hat Enterprise Linux.

Comment 3 RHEL Program Management 2012-07-11 02:09:25 UTC

This request was erroneously removed from consideration in Red Hat Enterprise Linux 6.4, which is currently under development.  This request will be evaluated for inclusion in Red Hat Enterprise Linux 6.4.

Comment 4 RHEL Program Management 2012-07-16 22:50:45 UTC

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

Comment 6 Adam Jackson 2012-09-10 21:12:38 UTC

4850544 build (rhel-6.4-xorg-rebase, /rpms/xorg-x11-drv-vesa:59b2c21e685ea8c63006e34d86863dda0ea463f4) completed successfully

MODIFIED

Comment 10 errata-xmlrpc 2013-02-21 08:04:45 UTC

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

http://rhn.redhat.com/errata/RHEA-2013-0301.html