DragonFly kernel List (threaded) for 2004-07
> Matthew Dillon wrote:
>> :4) If I'm not wrong DMA for CD drives is disabled by default. This
>> :means that the installation from the CD takes more time than it
>> :could. I think that setting somewhere in the installer sysctl
>> :hw.ata.atapi_dma="1" could improve the CD drive throughput and
>> :reduce the time needed.
>> As Joerg indicates, ATAPI DMA is fraught with compatibility
>> issues and, besides, I really doubt that that turning on DMA would
>> make the CD go any faster. CD transfer rates (even on 50x drives)
>> are quite slow and the real bottleneck is track seeking, which is
>> ultra slow on any CD drive.
> I wish I could agree, but when one does CD burning, DMA is extremely
> helpful in keeping the system reponsive and can dramatically increase
> performance. I think you'll hear the same thing echoed by many who do
> CD burning.
Which has nothing to do with the subject under discussion. :) The
original poster was asking for ATAPI DMA to be enabled *during the
installation process* to speed up the install from CD. This would
require quite a bit of work to get to operate correctly across all
hardware, and the end result wouldn't really be all that great.
Having ATAPI DMA enabled in the installed system, though, may be
something worth looking at. But for the actual install itself,
Freddie Cash, CCNT CCLP Helpdesk / Network Support Tech.
School District 73 (250) 377-HELP [377-4357]