Bug 26816

Summary: AGP KMS x11 video perf problem.
Product: DRI Reporter: Andy Furniss <adf.lists>
Component: DRM/RadeonAssignee: Default DRI bug account <dri-devel>
Status: RESOLVED DUPLICATE QA Contact:
Severity: normal    
Priority: medium CC: nobled
Version: XOrg git   
Hardware: x86 (IA32)   
OS: Linux (All)   
Whiteboard:
i915 platform: i915 features:
Attachments:
Description Flags
pool allocator to improve AGP performance. none

Description Andy Furniss 2010-03-01 05:05:43 UTC 
RV670 AGP running git ddx, xserver, libdrm and drt + nopat/AGP ttm caching fix patch. Problem is not new.

I think there is a caching problem with KMS that does not happen with UMS which makes video that doesn't use xv like flash or mplayer -vo x11 eat too much Cpu.

A partial work around can be achieved by disabling accel UTS, but it's still not as good as UMS.

Some top figures - this is with mplayer -vo x11 704x576@25fps Cpu is single core 2.1GHz.

UMS

Cpu(s): 18.7%us,  2.3%sy,  0.0%ni, 79.0%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
2504 andy      40   0 39008  13m 7748 S 13.3  1.5   0:01.10 mplayer
2472 root      40   0  591m 8508 5872 S  7.3  0.9   0:02.51 Xorg

KMS + ExaNoUploadToScreen

Cpu(s): 36.3%us,  0.3%sy,  0.0%ni, 63.3%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
4955 root      40   0 21140 9052 5760 S 22.9  1.0   0:04.76 Xorg
5006 andy      40   0 37980  13m 7836 S 13.6  1.5   0:00.71 mplayer

KMS

Cpu(s): 17.9%us, 60.8%sy,  0.0%ni, 21.3%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
4897 root      40   0 19628 8684 6040 R 65.8  1.0   0:29.11 Xorg
4925 andy      40   0 37980  13m 7836 S 13.0  1.5   0:00.91 mplayer

Will try and get a useful sysprof current effort just says in kernel for the last case.
Comment 1 Pauli 2010-03-01 07:10:03 UTC 
Created attachment 33664 [details] [review]
pool allocator to improve AGP performance.

Does this kernel patch help your performance problems? It is made against vanila git sources.

To profile kernel you will need 1.1.5 version of sysprofile and kernel debug symbols.
Comment 2 Andy Furniss 2010-03-01 09:32:01 UTC 
(In reply to comment #1)
> Created an attachment (id=33664) [details]
> pool allocator to improve AGP performance.
> 
> Does this kernel patch help your performance problems? It is made against
> vanila git sources.

Yes, that does fix it, KMS with UTS enabled is now the same as UMS.

KMS + ExaNoUploadToScreen is unchanged.

> To profile kernel you will need 1.1.5 version of sysprofile and kernel debug
> symbols.

Ahh, I was hoping to get away with the stable as I can't compile the newer one - it doesn't like my old gtk AFAICT.
Comment 3 Alex Deucher 2010-03-09 11:38:22 UTC 

*** This bug has been marked as a duplicate of bug 26641 ***

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