[Nottingham] Extreme partitioning [was: RAID stripe size?]

[Martin]

On 16/05/12 17:14, Jason Irwin wrote:
> On 16/05/12 16:53, Jason Irwin wrote:
>> I just remembered about this.  Does it apply to spinning platters as
>> well as to SSDs?
> To answer myself; yes, yes it does.  See this like originally posted by
> Martin:
> http://en.wikipedia.org/wiki/Advanced_format
> 
>> And if it does, how does one check things at a fine enough level to see
>> what is going on?
> Turns out the drives I have are "Advanced Format" which I didn't expect
> and there's no logo or anything on the drive to tell you.  I only found
> out from the tech specs on the Seagate site.
> 
> So it seems I should be concerned about this.  Any tools to help?

If you are using a recent distro and recent tools, then you should have
no worries. The 4kByte alignment has been known about for some time and
things have been patched to stay aligned. For example, various tools
align to 1MiB boundaries whether you want them to or not! Even your swap
space should be fine being as swap writes are in 4kiB pages for normal
Linux kernels.

Just for the sake of paranoia, perhaps keep away from using fdisk with
its old dos "chs" ways...

A GPT partition table is the way to go for partitioning.

Or don't partition at all and use the entire device.

Even LVM has been aligned since a rant by Ted T'so some time ago...


Best way is to do your stuff and then check what boundaries have
actually been used!

Good luck,

And see ya later,

Cheers,
Martin

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