Changes to support of Gallium 0.4 makes graphics very slow

[John Winterton]

Description: Ubuntu 14.10
Release: 14.10
xorg:
  Installed: 1:7.7+7ubuntu2
  Candidate: 1:7.7+7ubuntu2
  Version table:
 *** 1:7.7+7ubuntu2 0
        500 http://ca.archive.ubuntu.com/ubuntu/ utopic/main amd64 Packages
        100 /var/lib/dpkg/status

A change in the last week with automatic updates has changed the support of Gallium 0.4 on my RS780 chip set to
Gallium 0.4 on llvmpipe (LLVM 3.5, 128 bits). The result is that graphics response is considerably (visibly) slowed by the introduction of this interpreter. Further LLVM and its supporting components were not loaded.

One wonders if any kind of testing was done on this anywhere in the upstream side, or it was just believed that this was "better". I can assure you it is worse.

The worst effect is on full screen "games". The frame rate has dropped off to something like one per second or worse when running with wine. Native mode programs are also noticeably affected, in particular Libre Office Calc spreadsheets.

I did look up this new approach in so far as I am able using the synaptic program, and discovered that LLVM was not loaded. Naively, I loaded it with its related components. There is no visible improvement.

I need a work-around or a fix for this ASAP. My system is now very close to disabled.

ProblemType: Bug
DistroRelease: Ubuntu 14.10
Package: xorg 1:7.7+7ubuntu2
ProcVersionSignature: Ubuntu 3.16.0-28.38-generic 3.16.7-ckt1
Uname: Linux 3.16.0-28-generic x86_64
.tmp.unity.support.test.1:

ApportVersion: 2.14.7-0ubuntu8
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: compiz
CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0'
CompositorUnredirectFSW: true
CurrentDesktop: Unity
Date: Thu Dec 18 16:17:13 2014
DistUpgraded: Fresh install
DistroCodename: utopic
DistroVariant: ubuntu
ExtraDebuggingInterest: No
GraphicsCard:
 Advanced Micro Devices, Inc. [AMD/ATI] RS780L [Radeon 3000] [1002:9616] (prog-if 00 [VGA controller])
   Subsystem: Gigabyte Technology Co., Ltd Device [1458:d000]
InstallationDate: Installed on 2012-10-22 (786 days ago)
InstallationMedia: Ubuntu 12.10 "Quantal Quetzal" - Release amd64 (20121017.5)
MachineType: Gigabyte Technology Co., Ltd. GA-MA78LM-S2H
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.16.0-28-generic root=UUID=2c4c6961-8d74-4706-8d27-4c2226abc128 ro quiet splash vt.handoff=7
SourcePackage: xorg
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 04/16/2010
dmi.bios.vendor: Award Software International, Inc.
dmi.bios.version: F10
dmi.board.name: GA-MA78LM-S2H
dmi.board.vendor: Gigabyte Technology Co., Ltd.
dmi.board.version: x.x
dmi.chassis.type: 3
dmi.chassis.vendor: Gigabyte Technology Co., Ltd.
dmi.modalias: dmi:bvnAwardSoftwareInternational,Inc.:bvrF10:bd04/16/2010:svnGigabyteTechnologyCo.,Ltd.:pnGA-MA78LM-S2H:pvr:rvnGigabyteTechnologyCo.,Ltd.:rnGA-MA78LM-S2H:rvrx.x:cvnGigabyteTechnologyCo.,Ltd.:ct3:cvr:
dmi.product.name: GA-MA78LM-S2H
dmi.sys.vendor: Gigabyte Technology Co., Ltd.
version.compiz: compiz 1:0.9.12+14.10.20140918-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.56-1
version.libgl1-mesa-dri: libgl1-mesa-dri 10.3.0-0ubuntu3
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 10.3.0-0ubuntu3
version.xserver-xorg-core: xserver-xorg-core 2:1.16.0-1ubuntu1.2
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.9.0-1ubuntu2
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.4.0-2ubuntu2
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.914-1~exp1ubuntu4.1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.11-1ubuntu2
xserver.bootTime: Thu Dec 18 09:32:21 2014
xserver.configfile: default
xserver.errors:

xserver.logfile: /var/log/Xorg.0.log
xserver.version: 2:1.16.0-1ubuntu1.2
xserver.video_driver: radeon

[John Winterton (jwinterton)]

This problem disappeared overnight. The system was left running. I confess to being mystified by this.

[John Winterton (jwinterton)]

Fine. I've had one more incident which was cleared by a system boot.