Am 22.11.2012 15:46, schrieb Mark Nelson:
I haven't played a whole lot with SSD only OSDs yet (other than noting
last summer that iop performance wasn't as high as I wanted it). Is a
second partition on the SSD for the journal not an option for you?
Haven't tested that. But does this makes sense? I mean data goes to Disk
journal - same disk then has to copy the Data from part A to part B.
Why is this an advantage?
Stefan
Mark
On 11/22/2012 08:42 AM, Stefan Priebe - Profihost AG wrote:
Am 22.11.2012 15:37, schrieb Mark Nelson:
I don't think we recommend tmpfs at all for anything other than playing
around. :)
I discussed this with somebody frmo inktank. Had to search the
mailinglist. It might be OK if you're working with enough replicas and
UPS.
I see no other option while working with SSDs - the only Option would be
to be able to deaktivate the journal at all. But ceph does not support
this.
Stefan
On 11/22/2012 08:22 AM, Stefan Priebe - Profihost AG wrote:
Hi,
can someone from inktank comment this? Might be using /dev/ram0 with an
fs on it be better than tmpfs as we can use dio?
Greets,
Stefan
----- Mail original -----
De: "Stefan Priebe - Profihost AG" <s.priebe@xxxxxxxxxxxx>
À: "Sébastien Han" <han.sebastien@xxxxxxxxx>
Cc: "Mark Nelson" <mark.nelson@xxxxxxxxxxx>, "Alexandre DERUMIER"
<aderumier@xxxxxxxxx>, "ceph-devel" <ceph-devel@xxxxxxxxxxxxxxx>,
"Mark Kampe" <mark.kampe@xxxxxxxxxxx>
Envoyé: Jeudi 22 Novembre 2012 14:29:03
Objet: Re: RBD fio Performance concerns
Am 22.11.2012 14:22, schrieb Sébastien Han:
And RAMDISK devices are too expensive.
It would make sense in your infra, but yes they are really expensive.
We need something like tmpfs - running in local memory but support
dio.
Stefan
--
To unsubscribe from this list: send the line "unsubscribe ceph-devel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
