Re: PATA-disk named sda

From: Alan Cox
Date: Fri Jul 06 2007 - 11:13:59 EST


> So, the name of the drive can depend on something which happens in the
> ramdisk environment. Does anybody know what that is? And is there a
> kernel command line parameter which restores the old behaviour?

Old IDE -> /dev/hd*
LibATA -> /dev/sd*

so if you build both sets of modules it depends who gets loaded first.

> And what about hdparm (setting 32bit I/O and multi-sector mode)? Suren
> wrote that 32bit I/O makes no sense when using DMA. Maybe that's right,
> but it does not correspond with my experiences. At least, I have the
> "feeling" that my IDE disks work much faster since I enabled 32bit
> support (DMA already was on before).

32bit I/O and multi-sector I/O are PIO specific features - they have no
effect on DMA performance. 32bit is on my todo list but very low priority
as for most systems it makes almost no difference.

Alan
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