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From: andy thomas <andy@time-domain.co.uk>
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To: Albert Shih <Albert.Shih@obspm.fr>
Subject: Re: How many ram...
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On Tue, 13 Jan 2015, Albert Shih wrote:

> Hi all,
>
> Basic question : How many amount of ram I need for running ZFS with a pool
> of ~500-600To.
>
> For example If I've a server with 2 disk array of 60 disk of 6To.
>
> Is the rule I find somewhere on Internet saying for ZFS 1To --> 1Go is
> still true ?

I've have been running lots of HP Microservers fitted with 4 x 4 Tb disks 
in ZFS RAIDz1 under 8 GB of RAM for the past 3 years or so with no 
problems at all.

I've also got a SAN with 8 GB memory in the head node and 6 servers - each 
with 4 x 4 TB disks, RAIDz1 and 8 GB memory - attached as iSCSI VDEVs for 
a usable capacity of 50 TB. Again with no problems at all. Both set-ups 
break most of the rules in the rule-book but... it works!

Andy

----------------------------
Andy Thomas,
Time Domain Systems

Tel: +44 (0)7866 556626
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