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Re: 4k sector disks

On Wed, Sep 03, 2014 at 11:07:32AM +0100, Robert Swindells wrote:
> Is there any special configuration needed to use 4k sector disks
> efficiently ?
> I have a couple of SATA drives with 4k sectors, the disklabels for
> them give a sector size of 512 bytes but 'atactl identify' shows
> the true sector size.
> I used 'newfs -S 4096' on one of them, a new SSD, but am wondering
> whether to copy stuff off the other one and repartition.

(as stated elsewhere, label it with 512 byte sectors)

If it is an SSD the actual sector size is likely to be much higher than 4k.

I can't actually imagine an SSD emulating 512 byte sectors in 4k ones
and then doing the required RMW cycles (with wear leveling) that the
actual memory requires.

OTOH doing larger (aligned) transfers will help.

I'd certainly ensure that everything is aligned and that the fragment
and block sizes are large.
But remember the boot code doesn't have enough memory for very large blocks.


David Laight:

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