Re: I/O topology fixes for big physical block size

Jens Axboe
2010-09-28T04:30:34Z

On 2010-09-28 08:15, Mike Snitzer wrote:
> On Mon, Sep 27 2010 at 6:36pm -0400,
> Martin K. Petersen <martin.petersen@oracle.com> wrote:
>
>>>>>>> "Jens" == Jens Axboe <jaxboe@fusionio.com> writes:
>> Jens> Does mkfs do the right thing?
>>
>> Depends on which mkfs it is. Mike has tested things and can chip in
>> here...
>
> I haven't test all mkfs.* but...
>
> mkfs.xfs just works with 1M physical_block_size.
>
> mkfs.ext4 won't by default but -F "fixes" that:
>
> # mkfs.ext4 -b 4096 -F /dev/mapper/20017380023360006
> mke2fs 1.41.12 (17-May-2010)
> Warning: specified blocksize 4096 is less than device physical sectorsize 1048576, forced to continue

OK, so that's not exactly doing the right thing, but at least you can
work around it with a parameter. So I'd say that is good enough.

> I'll check fdisk and parted tomorrow (I know lvm2 doesn't look at
> physical_block_size).

Thanks!

--
Jens Axboe