slow probe for ata channel with only an atapi master on it
bde at zeta.org.au
Mon Jan 5 09:18:54 PST 2004
> The other drive is undead. It seems to fail to spin up sometimes, but
> works perfectly if its probe succeeds and I start accessing it immediately,
> but tends to fail if I don't access it for a while. It now always fails
> overnight. I'm wondering if it spins down and then the spin up doesn't
> work, and plan to try putting it in sleep modes intentionally. The
I tried your "atacontrol sleep" command. It broke the drive in much the
same way as not using it overnight, except the BIOS was able to wake
it up correctly :-). "atacontrol standby" doesn't break it.
> driver handles its failure poorly. The failure is usually hard (takes
> several power cycles to recover from), to it gets "removed from
> configuration" after several seconds or minutes of the system being
> unusable because it is blocked on Giant. Then removal usually causes
> a null pointer panic.
"atacontrol detach" also puts the drive too sleep, and it works much
better than shooting an active drive. It also works to help wake up the
drive: the drive works right after "atacontrol sleep; atacontrol detach;
atacontrol attach", except it takes about 5 seconds to wake up after
the first i/o command (attach apparently doesn't wake it up).
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