[arch-general] GPT slower than MBR, although both are properly aligned?

[Mauro Santos]

On 22-01-2011 22:49, Karol Babioch wrote:
> No, you are right, for SSDs the alignment is only important for writing,
> as whole blocks of "sectors" get erased and have to be rewritten. At
> least I've read that somewhere.
> 
> However, this doesn't explain my weird results, because hdparm -tT
> shouldn't write anything to the disk, should it?

Hdparm shouldn't and doesn't write anything to disk as far as I know,
that is why I said that something else must be interfering and gets you
the results you presented.

I have to agree with you that when using SSDs or newer drives with 4kB
sectors but with 512B sectors emulation it is not very easy to get the
alignment right. Maybe things will improve once the drives can report
the true minimum sector size they use for writing, which I guess they
should start doing soon or it will be a hidden bloody mess for everyone :p

-- 
Mauro Santos