OSD sizes

OSD sizes

[Gandalf Corvotempesta]

I'll run a testbed environment made with 3 or 5 DELL R515 servers (12
disks each).
I have no 10gb ethernet but only multiple LACP (2 or 4 gigabit nic)
I'll have two different networks, one for sync, one for client access.

In this case, i think that smaller disks are better, because in case
of failure of a single osd/disk the sync time will be less than a
bigger disk.

For example 12 500GB disks instead 12 3TB disks (the space is not an
issue, actually)

Re: OSD sizes

[Sébastien Han]

Hi,

As far I'm concerned I think that 12 disks per servers is way too much.
--
Bien cordialement.
Sébastien HAN.


On Wed, Oct 31, 2012 at 11:13 PM, Gandalf Corvotempesta
<gandalf.corvotempesta@gmail.com> wrote:
> I'll run a testbed environment made with 3 or 5 DELL R515 servers (12
> disks each).
> I have no 10gb ethernet but only multiple LACP (2 or 4 gigabit nic)
> I'll have two different networks, one for sync, one for client access.
>
> In this case, i think that smaller disks are better, because in case
> of failure of a single osd/disk the sync time will be less than a
> bigger disk.
>
> For example 12 500GB disks instead 12 3TB disks (the space is not an
> issue, actually)
> --
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Re: OSD sizes

[Denis Fondras]

Hello,

>
> As far I'm concerned I think that 12 disks per servers is way too much.

 From your experience, what is the "correct" number of OSD per server ?

Denis

Re: OSD sizes

[Sébastien Han]

Well, there is not really an "ideal" number. For instance, at
Dreamhost they put 12 disks per machines, but they have really big and
powerful server. The  problem is: as many disks per machine you have
as data you have to migrate in case of failure. At the end, it's up to
you... It also highly depend of the size of your cluster (amount of
data).
--
Bien cordialement.
Sébastien HAN.


On Sun, Nov 4, 2012 at 10:41 AM, Denis Fondras <ceph@ledeuns.net> wrote:
> Hello,
>
>
>>
>> As far I'm concerned I think that 12 disks per servers is way too much.
>
>
> From your experience, what is the "correct" number of OSD per server ?
>
> Denis
>
> --
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