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Subject: Re: DOS by unprivileged user
From:   Mike Galbraith <efault@gmx.de>
To:     Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Cc:     Ferry Toth <ftoth@telfort.nl>, linux-kernel@vger.kernel.org
Date:   Wed, 25 Apr 2018 18:50:33 +0200
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On Wed, 2018-04-25 at 15:54 +0100, Alan Cox wrote:
> 
> Classical Unix systems never had this problem because they respond to
> thrashing by ensuring that all processes consumed CPU and made some
> progress. Linux handles it by thrashing itself to dealth while BSD always
> handled it by moving from paging more towards swapping and behaving like
> a swap bound batch machine.

Memcg constrained the gitk hog nicely, forcing it do dig into swap
after hitting its limit.  Dunno if there are any userspace bits that
can use it wisely though.

	-Mike