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Date: Mon, 4 Nov 2013 16:23:34 +0000
Message-ID: <CAFHbX1+TSrPJBkaHTdi7QbB-vKQqwU3W_cYwD2PCuc+OrN-+3g@mail.gmail.com>
Subject: Re: Reality check? compat.ia32.maxdsiz in jailed "32-bit" environment
From: Tom Evans <tevans.uk@googlemail.com>
To: David Wolfskill <david@catwhisker.org>
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On Mon, Nov 4, 2013 at 3:49 PM, David Wolfskill <david@catwhisker.org> wrot=
e:
> I am supporting a performance-sensitive software development
> environment that:
> =E2=80=A6
> I have (also) started experimenting with increasing compat.ia32.maxdsiz
> beyond its default of 512MB: Initially, I kicked it to 2GB; more
> recently, I tried setting it to 3GB.
>
> While I have not noticed any negative issues from either of the above
> non-default settings, I have done but limited testing with concurrent
> software builds in my test environment.

IIRC, when running on pure i386, setting kern.maxdsiz limits the
amount of kernel address space (or rather, dsize+KVA =3D 4 GB), and so
you had to be careful when increasing kern.maxdsiz.

This probably has no effect on a i386 on amd64 jail though.

Cheers

Tom