Re: DragonFly faster than linux or FreeBSD?

[Rahul Siddharthan <rsidd@xxxxxxxxx>]

Matthew Dillon said on Jun 16, 2004 at 13:57:22:
>     Heavy I/O activity should only really have a 'glitch' effect in regards
>     to processes competing for disk I/O.  

Well, the things I mentioned -- audio playback, opening a new xterm --
do disk I/O (at least the I part), though not the mouse pointer and
keyboard echo -- and in fact the latter freeze only under extreme
conditions.


>     Other possibilities include overheads
>     that occur if (e.g.) your IDE drive is not operating in a DMA mode.
> 
>     You can query the DMA modes with 'atacontrol'.  e.g. on my AMD-XP box:

Thanks for info -- I was using sysctl, didn't know atacontrol could do
this.  Anyway, DMA is turned on for my hard drive, off for my CD
drive.

If I try turning DMA on for my CD drive, btw, I get no complaints
initially, but error messages when I try to play a DVD:
acd0: CD-RW <QSI CD-RW/DVD-ROM SBW-241> at ata1-master PIO4
acd0: READ_BIG - NO SENSE asc=0x00 ascq=0x00 error=0x00
acd0: READ_BIG - NOT READY asc=0x00 ascq=0x01 error=0x00

With DMA off, the DVD reads fine but plays choppily.  Linux with DMA
on has no problem on the same machine.  I don't think I've tried
FreeBSD.

Rahul