Re: inode64 mount option for XFS

[Wido den Hollander <wido@42on.com>]

On 11/03/2014 01:34 PM, Stefan Priebe - Profihost AG wrote:
> 
> Am 03.11.2014 um 13:28 schrieb Wido den Hollander:
>> Hi,
>>
>> While look at init-ceph and ceph-disk I noticed a discrepancy between them.
>>
>> init-ceph mounts XFS filesystems with rw,noatime,inode64, but
>> ceph-disk(-active) with rw,noatime
>>
>> As inode64 gives the best performance, shouldn't ceph-disk do the same?
>>
>> Any implications if we add inode64 on running deployments?
> 
> Isn't inode64 XFS default anyway?
> 

The XFS website suggests it isn't:
http://xfs.org/index.php/XFS_FAQ#Q:_What_is_the_inode64_mount_option_for.3F

"By default, with 32bit inodes, XFS places inodes only in the first 1TB
of a disk."

However, if you look at bit further:
http://xfs.org/index.php/XFS_status_update_for_2012

"Linux 3.7 will be a fairly boring release as far as XFS is concerned,
the biggest user visible changes are an intelligent implementation of
the lseek SEEK_HOLE/SEEK_DATA calls, and finally the switch to use the
inode64 allocator by default. "

So it seems you are partially right. It depends on the kernel you are
running if it is enabled by default.

Wido

> Stefan
> 
> --
> To unsubscribe from this list: send the line "unsubscribe ceph-devel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 


-- 
Wido den Hollander
42on B.V.
Ceph trainer and consultant

Phone: +31 (0)20 700 9902
Skype: contact42on