Unusual Question

Steve O'Hara-Smith steve at sohara.org
Mon Jul 10 15:34:08 UTC 2017


On Mon, 10 Jul 2017 10:26:25 -0500 (CDT)
"Valeri Galtsev" <galtsev at kicp.uchicago.edu> wrote:

> I believe, the kernel addresses swap not by addressing sectors on raw
> device covering the whole physical drive, but as "relative sectors"
> through swap partition device.

	Sure, but I doubt it reads the partition table again after it has
it read the first time, that's an obvious thing to cache.

> If I'm right, once drive partition table is
> gone reading swap will fail and panic kernel.

	I doubt it, the partition table should be cached in memory,
otherwise yes that would panic the kernel, but reading the partition table
every time a page needs swapping in would be stupidly inefficient so I
don't believe it happens.

> But the suggestion you made in another post: to make

	Not my suggestion, it's a sensible one but I don't think it's
needed.

-- 
Steve O'Hara-Smith                          |   Directable Mirror Arrays
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