Re: [Qemu-devel] [PATCH] -win2k-hack performance+DMA support

[Brad Campbell]

Leonardo E. Reiter wrote:
> Attached is a patch which greatly speeds up disk writes when using 
> -win2k-hack to install Windows 2000.  It only delays every 16th 
> interrupt, which after rigorous testing is still enough to overcome the 
> "Windows 2000 disk full" bug.  If you are really adventurous you can try 
> it every 32nd time, but for me that caused problems during some 
> installations, so I thought it was too aggressive.
>
> This patch also adds -win2k-hack functionality to DMA writes, since DMA 
> now works in the latest CVS QEMU.

Using todays CVS, and kqemu in user mode only I tried to install Win2k-SP4 25 times all with disk 
full errors until I applied this patch.
It would appear the installer will use DMA mode if it's available and therefore the existing 
win2k-hack does not work.

Using this patch 5 out of 5 installs worked perfectly.

Thanks Leo :)

Regards,
Brad
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