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Date: Tue, 13 Jan 2015 13:04:02 +0100
From: Robert David <robert@linsystem.net>
To: Albert Shih <Albert.Shih@obspm.fr>
Subject: Re: How many ram...
Message-ID: <20150113130402.7b6468b6@linsystem.net>
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Hi Albert,

it mainly depends how you will use this pool. If it would be some cold
storage used only for slow backups, then somehow reasonable amount of
ram is ok. Let say 32GB can work.
The main problem is with performance, since ram affect zfs a lot (after
warming period).

If it will be some performance data storage, 256GB ram can be not that
much.

Also do not use deduplication on such pools or you will find any amount
of memory too low. I would say, do not use deduplication on any pool,
even the small ones.

Regards,
Robert.=20

On Tue, 13 Jan 2015 11:52:40 +0100
Albert Shih <Albert.Shih@obspm.fr> wrote:

> Hi all,
>=20
> Basic question : How many amount of ram I need for running ZFS with a
> pool of ~500-600To.
>=20
> For example If I've a server with 2 disk array of 60 disk of 6To.
>=20
> Is the rule I find somewhere on Internet saying for ZFS 1To --> 1Go is
> still true ?
>=20
> What's happen If I use less ram ? Like 1To --> 0.5Go ? Less
> performance ? crash ?
>=20
> Regards.
>=20
> JAS
>=20
> --
> Albert SHIH
> DIO b=C3=A2timent 15
> Observatoire de Paris
> 5 Place Jules Janssen
> 92195 Meudon Cedex
> France
> T=C3=A9l=C3=A9phone : +33 1 45 07 76 26/+33 6 86 69 95 71
> xmpp: jas@obspm.fr
> Heure local/Local time:
> mar 13 jan 2015 11:49:16 CET
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