Partition for OSD journal

Partition for OSD journal

[Madhusudhana U]

Hi all,
I read in the wiki that, to have a better performance compared to file
under OSD data dir, we can have a seperate partition for OSD journal.
can someone suggest me, how i can mention this in ceph.conf file ?
I have below lines in my ceph.conf file. Is this means I already have
a partition for OSD journal

[osd]
        osd data = /data/osd.$id
        keyring = /etc/ceph/keyring.$name
        osd journal = /journal/osd.$id.journal

/journal is a separate partition of 20G.

Thanks
__M

Re: Partition for OSD journal

[Stefan Kleijkers]

Hello,

Just partition the disk, like sda1, sda2, etc and add the following to 
your config:
[osd.0]
             osd journal = /dev/sda1

[osd.1]
             osd journal = /dev/sda2

etc...

So you can point the "osd journal" to a file or to a device.

The negative side to this is you have to partition the disk and have to 
add a different option for every osd. You could fix this with udev and 
make a logical naming scheme for the device like:
/dev/osd.0.journal
/dev/osd.1.journal
etc

That way you can add to your config:
[osd]
             osd journal = /dev/osd.$id.journal

Stefan

On 04/12/2012 06:22 PM, Madhusudhana U wrote:
> Hi all,
> I read in the wiki that, to have a better performance compared to file
> under OSD data dir, we can have a seperate partition for OSD journal.
> can someone suggest me, how i can mention this in ceph.conf file ?
> I have below lines in my ceph.conf file. Is this means I already have
> a partition for OSD journal
>
> [osd]
>          osd data = /data/osd.$id
>          keyring = /etc/ceph/keyring.$name
>          osd journal = /journal/osd.$id.journal
>
> /journal is a separate partition of 20G.
>
> Thanks
> __M
>
> --
> 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
>