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From: Wim Lewis <wiml@omnigroup.com>
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Subject: ZFS pool with a large number of filesystems
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Date: Mon, 4 Apr 2016 17:38:30 -0700
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I'm curious how many ZFS filesystems are reasonable to have on a single =
machine (in a single zpool). We're contemplating a design in which we'd =
have tens of thousands, perhaps a couple hundred thousand, filesystems =
mounted out of the same pool. Before we go too far into investigating =
this idea: Does anyone have real-world experience doing something like =
that? Is it a situation that ZFS-on-FreeBSD is engineered to handle with =
good performance? Is there a rough estimate of the resources consumed =
per additional filesystem (in terms of kernel VM and disk space)?

Thanks for any insight or advice (even, or especially, if the answer is =
"that's crazy, don't do that" :) )


Wim Lewis / wiml@omnigroup.com