APM problem in 5.1-RELEASE

[Jesse Guardiani]

Jesse Guardiani wrote:

> Jesse Guardiani wrote:
> 
>> Jesse Guardiani wrote:
>> 
>>> Darryl Okahata wrote:
>>> 
>>>> Jesse Guardiani <jesse at wingnet.net> wrote:
>> 
>> [...]
>> 
>>> Now, if I can just get that lousy CD-ROM to not crash my system on
>>> resume I'll be a VERY happy man...


I did some more testing on this last night, and it appears that
the atacontrol detach method _does_ work, but only in specialized
circumstances.

I have modified my /etc/rc.suspend to call 'atacontrol detach 1'
_before_ it calls 'apm -z'. I have also modified my /etc/rc.resume
to call 'atacontrol attach 1' _after_ syncing the disks. If anyone
wants to have a look at these files, just let me know.

When it works:
--------------
1.) I have to be looking at a VTY, not X. (Geez. Just when I thought
    I got around this with the kernel option SC_NO_SUSPEND_VTYSWITCH...)

2.) The /dev/acd0 device has to be unused, otherwise the kernel panics.
    This means I have to stop playing any CDs and terminate the CD playing
    program. I assume this means that the device has to be _not_ open,
    but I haven't really performed much testing in this area.


When it doesn't work:
---------------------
1.) If I try to suspend while looking at X, the kernel panics and auto-
    reboots.

2.) If I try to suspend while anything is accessing the acd0 device the
     kernel panics and auto-reboots.


Those things aside, I can usually suspend my machine within 8 seconds, as
long as the hard disk isn't under high load. And it comes back on-line in
under 3 seconds. I've tested this 6 or 7 times in a row, swapping back and
forth from X before doing the next suspend, so I'm pretty confident that
it's reliable.

A plus is that the little green "drive in use" light on the side of my
Ultrabay goes off when the machine is in suspend mode, and since I call:

atacontrol attach 1

Upon resume from suspend, I could very easily swap out my drives while in
suspend mode. I've tested this. Pretty neat!


Things I would like to improve upon:
------------------------------------
1.) I need to find some way to automatically kill any processes that are
    using (or have opened) the /dev/acd0 device BEFORE executing apm -z
    from /etc/rc.suspend.

    If I can accomplish that, then I will have successfully eliminated the
    "stupid human" factor that sometimes causes me to forget I have a
    program running that uses the /dev/acd0 device.

    Does anyone have any ideas here?

2.) I'd love to automate (or do away with) the process of switching to
    a VTY from X before executing 'atacontrol detach 1'.

    Can anyone give me a _reason_ why I have to do that? It just seems
    odd to me.

Thanks!

-- 
Jesse Guardiani, Systems Administrator
WingNET Internet Services,
P.O. Box 2605 // Cleveland, TN 37320-2605
423-559-LINK (v)  423-559-5145 (f)
http://www.wingnet.net