Re: Disk write cache (Was: Hyper-Threading Vulnerability)

[Eric D. Mudama]

On 5/16/05, Matthias Andree <matthias.andree@xxxxxx> wrote:
> I've heard that drives would be taking rotational energy from their
> rotating platters and such, but never heard how the hardware compensates
> the dilation with decreasing rotational frequency, which also requires
> changed filter settings for the write channel, block encoding, delays,
> possibly stepping the heads and so on. I don't believe these stories
> until I see evidence.

I'm pretty sure that most drives out there will immediately attempt to
safely retract or park the heads the instant that a power loss is
detected.  There's too much potential damage that can occur if the
heads aren't able to safely retract to a landing zone or ramp, that
trying to save "one more block of cached data" just isn't worth the
risk.

--eric
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