Re: Generic Disk Driver in Linux

From: Helge Hafting
Date: Mon Aug 28 2006 - 06:47:50 EST


Aleksey Gorelov wrote:
--- Helge Hafting <helge.hafting@xxxxxxxxxxxxx> wrote:

Aleksey Gorelov wrote:
From: linux-kernel-owner@xxxxxxxxxxxxxxx [mailto:linux-kernel-owner@xxxxxxxxxxxxxxx] On Behalf Of Jan Engelhardt
I was curious that can we develop a generic disk driver that could
handle all the kinds of hard drives - IDE, SCSI, RAID et al?
ide_generic
sd_mod

All there, what more do you want?
Unfortunately, not _all_. DMRAID does not support all fake raids yet. Moreover, there is
usually
some gap for bleeding edge hw support.
Nobody will want to use bleeding edge hardware with an int13 driver,
because the performance will necessarily be much worse than using more
moderate hardware with the generic IDE driver.
If some one wants Linux server - I totally agree. I would probably even avoid relying purely on
generic IDE and instead use chipset specific variant or libata.
But if someone wants to access already installed & working other OS stuff - that's a different
story. Bad performance is still better than no support at all.
Yes, there is forensics, and there is the copying of data when
migrating a server to linux from some other OS.

Perhaps I worry too much - I imagine salesmen claiming linux
support for their raid cards, because the int13 driver works. Just like they claim "linux support" with abominations like ndiswrapper.
The bad effects may be carefully hidden with "disk" tests that are
smaller than main memory in some huge-memory machine.

Then linux gets a bad reputation among ignorant purchasers,
performance went so much up with some other os . . .

Helge Hafting

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