Re: libata question

[Roger Oberholtzer <roger@opq.se>]

On Wed, 2006-08-02 at 04:06 +0900, Tejun Heo wrote: 
> Roger Oberholtzer wrote:
> > On Wed, 2006-08-02 at 03:45 +0900, Tejun Heo wrote:
> >> Roger Oberholtzer wrote:
> >>> On Wed, 2006-08-02 at 00:33 +0900, Tejun Heo wrote:
> >>>> Roger Oberholtzer wrote:
> >>>>> Should hotplug work with Intel Corporation 82801GB/GR/GH (ICH7
> >>>>> Family) chipset? I am trying kernel 2.6.17.7
> >> Ah.. I should have spotted this earlier.  2.6.17.7 doesn't contain 
> >> updated EH and doesn't support any of new features including 
> >> hot/warmplug.  Please try 2.6.18-rc3.
> > 
> > OK. But I think there are issues with 2.6.18 generally. But I can try it
> > to see if this makes this better.
> 
> If you're uncomfortable with -rcX, you can try libata-tj-stable patch. 
> It contains most of new stuff.
> 
> http://home-tj.org/files/libata-tj-stable/libata-tj-2.6.17.4-20060710.tar.bz2

Thanks for that. But it had no noticeable difference.

I looked in the bios on my system to see if I could set the SATA disks
to AHCI mode. I did not see anything like that. I could select to do a
manual config, in which case I could set things like LBA mode, 32-bit
I/O (which defaults to off). So if hots wap require AHCI mode, I seem to
be screwed. It is a phoenix bios for the supermicro computer.

Maybe I can try a different SATA card instead of the stuff on the
motherboard. What do you think is the best one re hots waping? Either
PCI or PCI-X.

> >>> I bet the driver does the right thing. The trick is knowing what that is
> >>> supposed to be. And how to use the various commands on files in /sys at
> >>> the correct time and in the correct order.
> >> Really, it's not that complicated.
> > 
> > Once you know what it is you need to do.
> 
> I tried hard to make things just work.  If you find things unnecessarily 
> complicated, please let me know.

I have a system with an IDE disk with the OS that is fixed. I also have
4 hot swappable SATA disk bays. My use will involve changing the SATA
disks to do an analysis of the data they contain. There will be 4 disks
in an analysis set. I need to make it easy for the user to insert and
remove disks. Rebooting each time is a bad alternative. So, if hot swap
does not work, I will have to get warm swap working. I think part of the
confusion I have is how to deal with disks that are mounted. So I need
to get the steps well defined and make those that require user
interaction as few as possible.

-- 
Roger Oberholtzer

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