I think 2 small ssds (raid 1 mdadm) can do the job better as ssds have lower latencies .You can use them both for OS (minimum needed is 60 GB) and the rest will be plenty for an arbiter.
By the way, if you plan using gluster snapshots - use thin LVM for the brick.

Best Regards,
Strahil Nikolov

On Apr 24, 2019 16:20, Leo David <leoalex@gmail.com> wrote:
Hello Everyone,
I need to look into adding some enterprise grade sas disks ( both ssd and spinning  ),  and since the prices are not too low,  I would like to benefit of replica 3 arbitrated.
Therefore,  I intend to buy some smaller disks for use them as arbiter brick.
My question is, what performance ( regarding iops,  througput ) the arbiter disks need to be. Should they be at least the same as the real data disks ?
Knowing that they only keep metadata, I am thinking that will not be so much pressure on the arbiters.
Any thoughts?

Thank you !


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Best regards, Leo David