SSD drives

[Oleg Goldshmidt]

On Sun, Dec 30, 2012 at 8:46 AM, shimi <linux-il at shimi.net> wrote:
>
> I really don't think so. SSDs (IMHO) makes computer much faster due to the
> VERY low seek time - the time it takes you to get a block. Compare 10-20ms
> with ~0.1ms. A regular hard drive simply wastes a lost of time seeking the
> data, instead of... reading it :)

Absolutely correct. However, there is a tiny fraction of the seek time
that is not always a waste, and I think it is worth mentioning. There
is, I believe, a consideration that is usually overlooked when SSDs
are considered for server use, including a "desktop" that is used as a
server, which is why I am mentioning it here. In a server, magnetic
disk rotation - or, rather the air turbulence generated between the
rotating disk and its enclosure - is the only source of entropy that
makes random numbers random (seek times have a tiny random component
due to the turbulence, and it is captured). This does not apply to
SSDs, and as a result your security may be compromised (attacks
exploiting not very random RNGs are well known).

In a laptop or a desktop entropy is also generated by keyboard and
mouse (which may or may not be good enough). In a server that hardly
applies.

-- 
Oleg Goldshmidt | pub at goldshmidt.org