Re: 2.6.x Scheduler, preemption and responsiveness - puzzlement

From: Sid Boyce
Date: Mon Jul 12 2004 - 04:21:17 EST


Con Kolivas wrote:

Sid Boyce writes:

Nuno Monteiro wrote:


On 2004.07.11 23:55, Sid Boyce wrote:

I've been wondering why this is, I can't remember what the BIOS says about the hard drives, from memory it looked OK, I think it was set to



<snip snip>

PCI IDE nVidia Corporation nForce2 IDE (rev a2)



<snip snip>

# CONFIG_BLK_DEV_AMD74XX is not set



You don't have the driver for your IDE chipset compiled in. In the "ATA/ ATAPI/MFM/RLL support" under "Device Drivers" menu select "AMD and nVidia IDE support". Also, you can disable the "Generic PCI IDE Chipset Support" and the "VIA82CXXX chipset support" you seem to have enabled.

Then you should be able to do DMA, and things will go a lot faster.


Hope this helps.



Nuno


Oops!, thanks. The previous motherboard used the VIA chipset, so that got missed when I changed over.
Regards
Sid.


DMA disabled is perhaps the most common reason for poor performance under I/O loads. I think some cut down configurations that people have used from their 2.4 installations have missed the appropriate IDE driver.

Cheers,
Con

That fixed the problem. When I checked my P-II 333 box and AMD64 laptop (VIA chipset), they were OK. Working on 4 boxes at the same time, I guess I got stuck in a VIA mental groove.
Regards
Sid.

--
Sid Boyce .... Hamradio G3VBV and keen Flyer
===== LINUX ONLY USED HERE =====

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