Go Back   nV News Forums > Linux Support Forums > NVIDIA Linux

Newegg Daily Deals

Reply
 
Thread Tools
Old 05-13-06, 03:10 AM   #1
ZicoTheTux
Registered User
 
Join Date: May 2004
Posts: 182
Default Low performance on SuSE 10.1 x86_64

Hi

Just installed SuSE 10.1 x86_64.
Compared to SuSE 10.0 (32 Bit) the dirver Performance is not even the half of what I had before (glxgreads drops from 17000 to 7500, games as well).
I use the newest nvidia driver (64Bit of course).
Tried all NvAGP settings.
dmesg keeps to tell me:
"NVRM: not using NVAGP, kernel was compiled with GART_IOMMU support!!"

Could this be a problem? If yes how to solve it?
I think it is a problem, because nvidia-settings tells me "Bus-Type: PCI", my GeForce 6800U is AGP model

zico@marvin:/proc/driver/nvidia/agp> cat /proc/driver/nvidia/agp/status
Status: Disabled

AGP initialization failed, please check the ouput
of the 'dmesg' command and/or your system log file
for additional information on this problem.


Looks bad. Is there a solution from the driver about that GART_IOMMU support or do I need to recompile the kernel?

Last edited by ZicoTheTux; 05-13-06 at 03:27 AM.
ZicoTheTux is offline   Reply With Quote
Old 05-13-06, 03:29 AM   #2
zander
NVIDIA Corporation
 
zander's Avatar
 
Join Date: Aug 2002
Posts: 3,740
Default Re: Low performance on SuSE 10.1 x86_64

@ZicoTheTux: you'll need to rebuild your kernel without GART_IOMMU if you wish to use NvAGP (only one of these may drive the K8 GART); this isn't necessary with the Linux AGPGART driver.
zander is offline   Reply With Quote
Old 05-13-06, 03:33 AM   #3
ZicoTheTux
Registered User
 
Join Date: May 2004
Posts: 182
Default Re: Low performance on SuSE 10.1 x86_64

Ok but is there an alternative to NvAGP?
As far as I see there is completly no AGP support on the whole system.
I see I can't use NvAGP but as you read above everything runs on PCI-mode.
Ok it is not the drivers problem but has my kernel no AGP support at all or does it just not work with the nvidia driver?
ZicoTheTux is offline   Reply With Quote
Old 05-13-06, 03:43 AM   #4
zander
NVIDIA Corporation
 
zander's Avatar
 
Join Date: Aug 2002
Posts: 3,740
Default Re: Low performance on SuSE 10.1 x86_64

@ZicoTheTux: you can use the Linux AGPGART driver; this is the default configuration (i.e. if you leave the NvAGP X driver option unset or set it to "2").
zander is offline   Reply With Quote
Old 05-13-06, 03:57 AM   #5
ZicoTheTux
Registered User
 
Join Date: May 2004
Posts: 182
Default Re: Low performance on SuSE 10.1 x86_64

Tried now NvAGP 2 and removed the option.
In both cases the performance stays very low.

zico@marvin:/proc/driver/nvidia/agp> cat /proc/driver/nvidia/agp/status
Status: Disabled

stays there.
I tried to use testgart, a program to test agpgart on my system but it tells me
open: No such file or directory

The device
/dev/agpgart is not there, too.
Something seems to be wrong here
ZicoTheTux is offline   Reply With Quote
Old 05-13-06, 04:10 AM   #6
zander
NVIDIA Corporation
 
zander's Avatar
 
Join Date: Aug 2002
Posts: 3,740
Default Re: Low performance on SuSE 10.1 x86_64

@ZicoTheTux: make sure you configured your kernel to include AGPGART support; with respect to /dev/agpgart, it's not used by the NVIDIA graphics driver (the NVIDIA kernel module interfaces with agpgart.ko directly).
zander is offline   Reply With Quote
Old 05-13-06, 04:37 AM   #7
ZicoTheTux
Registered User
 
Join Date: May 2004
Posts: 182
Default Re: Low performance on SuSE 10.1 x86_64

Ok I now recompile the kernel with agpgar support.. I'm sure it will solve that problem.
So as I understand it now it will not be possible to run the nvidia driver at full performance without agpgart support in the kernel, right?
I always liked the suse default kernel because I could install everything very fast. This GART_IOMMU makes everything a bit more complicated and not very user friendly. I hope there will be a way in the future to solve this.
ZicoTheTux is offline   Reply With Quote
Old 05-13-06, 05:16 AM   #8
zander
NVIDIA Corporation
 
zander's Avatar
 
Join Date: Aug 2002
Posts: 3,740
Default Re: Low performance on SuSE 10.1 x86_64

@ZicoTheTux: the IOMMU/AGPGART code and NvAGP need to own the same resource, the K8 GART, in order to work; with IOMMU/AGPGART support built into Linux/x86-64 kernels, NvAGP support thus can't be enabled. If you don't need the IOMMU (i.e. if you don't have any devices that require 32-bit addressable DMA memory), you can safely disable GART_IOMMU and use NvAGP.

Older NVIDIA Linux graphics drivers relied on the IOMMU exclusively to obtain 32-bit addressable DMA memory mappings; as of 1.0-8756, the IOMMU will only be used on Linux/x86-64 kernels older than Linux 2.6.15, and only if the GPU for which the memory is allocated can't address memory past the 4GB boundary (NVIDIA non-legacy PCI-E GPUs can). On Linux/x86-64 kernels >= Linux 2.6.15, the GFP_DMA32 zone will be used instead, and IOMMU/SWIOTLB support won't even be built into the driver.

That said, the NVIDIA Linux/x86-64 graphics driver relies on AGPGART for AGP support if the kernel was built with IOMMU/AGPGART support; if the kernel was built with IOMMU support, but without AGPGART support, AGP support will be unavailable, which can incur a significant performance penalty, depending on the application(s) used.
zander is offline   Reply With Quote

Old 05-13-06, 05:45 AM   #9
ZicoTheTux
Registered User
 
Join Date: May 2004
Posts: 182
Default Re: Low performance on SuSE 10.1 x86_64

Ah I understand it now.
As question if we are at this theme:
As you said 32Bit Kernels will not make use of this feature. Would you personally suggest to install a 32 Bit system on an AGP-based 64Bit machine? I ask if I wonder if there could be any other "bottlenecks" within a 64Bit kernel/system interferring with AGP devices.
ZicoTheTux is offline   Reply With Quote
Old 05-13-06, 05:56 AM   #10
zander
NVIDIA Corporation
 
zander's Avatar
 
Join Date: Aug 2002
Posts: 3,740
Default Re: Low performance on SuSE 10.1 x86_64

@ZicoTheTux: no, it isn't necessary to install a 32-bit Linux kernel/system to take full advantage of the AGP port.
zander is offline   Reply With Quote
Old 05-14-06, 11:34 PM   #11
ZicoTheTux
Registered User
 
Join Date: May 2004
Posts: 182
Default Re: Low performance on SuSE 10.1 x86_64

Ok I now finally had the time to recompile the kernel and played a bit around with the 32Bit version.
It works for NvAGP finally.
But I notice a performance drop since i upgraded from 8174 to 8756.
glxgears dropped from 16000 to 13000 and in my games I lost about 10 FPS (average). I wonder why this happens.
I tried a bit around by disbaling PREEMPT in the kernel, switching NvAGP modes and made sure FSAA and FSAF is disabled. But I still notice this Framedrop.

Here an example:
CPU: AMD64 3500+
Video: GeForce 6800Ultra

SuSE10 (32Bit), nvidia-8174, Doom3 timedemo usechache - Ultra details: 82FPS
SuSE10.1 (64Bit), nvidia-8756, Doom3 timedemo usechache - Ultra details: 72FPS
SuSE10.1 (32Bit), nvidia-8756, Doom3 timedemo usechache - Ultra details: 69FPS
strange
ZicoTheTux is offline   Reply With Quote
Reply


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


Similar Threads
Thread Thread Starter Forum Replies Last Post
My UT2003 Tweak Guide DXnfiniteFX Gaming Central 48 10-30-02 11:59 PM
Low OpenGL Performance Instinct NVIDIA Linux 10 08-08-02 03:56 PM

All times are GMT -5. The time now is 11:22 PM.


Powered by vBulletin® Version 3.7.1
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright 1998 - 2014, nV News.