What are the correct mkfs.xfs parameters for a lying WD-EARS HDD?

[Matthias Schniedermeyer]

On 08.03.2010 16:45, Eric Sandeen wrote:
> Matthias Schniedermeyer wrote:
> > Hi
> > 
> > 
> > More than a month ago i bought 4 Western Digital WD15EARS (1.5 TB) which 
> > are (AFAIK) the first general/commercial available 4k sector SATA-HDDs.
> > 
> > Unfortunatly the HDDs lie about the 4k physical sector size and the most 
> > prominent drawback is a worse than abysmal delete performance.
> > ("Normal" Read & Write-performance is OK)
> > 
> > So if i wanted to (re-)mkfs the filesystems what would the correct 
> > parameters be?
> > 
> > Kernel/Userspace is pretty recent (Debian-SID):
> > mkfs.xfs version 3.1.1, kernel v2.6.33, util-linux 2.16.0
> > Not that that should matter when the HDDs lies.
> 
> Recent kernel+util-linux-ng++fdisk+parted+xfsprogs -should- do the right thing for you....
> Oh, but this was maybe the drive that didn't output the right stuff when queried.

hdparm -I /dev/sdg | grep "Sector size"
        Logical/Physical Sector size:           512 bytes

hdparm -V
hdparm v9.27

I vagely remember a posting on LKML that said it's a "known problem" 
that the WD??EARS lie about physical sector size.

> Make sure your partitions, if any, are on 4k boundaries.(*)  older fdisk at least
> won't do this by default, not sure about parted.

It's an encrypted loop at am 4k offset to leave space for a fake MBR 
(and more importantly a signature for a custom udev-script).

> once that is done, tell mkfs.xfs "-s size=4096" to set the 4k sector size

So that should be enough?
Time for backup/mkfs/restore then.





Bis denn

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