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Date: Fri, 20 Jul 2018 18:41:59 +0000
From: Hugo Mills <hugo@carfax.org.uk>
To: Andrei Borzenkov <arvidjaar@gmail.com>
Cc: kreijack@inwind.it, Duncan <1i5t5.duncan@cox.net>,
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Subject: Re: [PATCH 0/4] 3- and 4- copy RAID1
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On Fri, Jul 20, 2018 at 09:38:14PM +0300, Andrei Borzenkov wrote:
> 20.07.2018 20:16, Goffredo Baroncelli =D0=BF=D0=B8=D1=88=D0=B5=D1=82:
[snip]
> > Limiting the number of disk per raid, in BTRFS would be quite simple to=
 implement in the "chunk allocator"
> >=20
>=20
> You mean that currently RAID5 stripe size is equal to number of disks?
> Well, I suppose nobody is using btrfs with disk pools of two or three
> digits size.

   But they are (even if not very many of them) -- we've seen at least
one person with something like 40 or 50 devices in the array. They'd
definitely got into /dev/sdac territory. I don't recall what RAID level
they were using. I think it was either RAID-1 or -10.

   That's the largest I can recall seeing mention of, though.

   Hugo.

--=20
Hugo Mills             | Have found Lost City of Atlantis. High Priest is
hugo@... carfax.org.uk | winning at quoits.
http://carfax.org.uk/  |
PGP: E2AB1DE4          |                                       Terry Pratch=
ett

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