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Date: Sun, 18 Nov 2018 17:53:52 +0100 (CET)
From: Wojciech Puchar <wojtek@puchar.net>
To: Stefan Blachmann <sblachmann@gmail.com>
cc: Cy Schubert <Cy.Schubert@cschubert.com>, Ian Lepore <ian@freebsd.org>,
 Wojciech Puchar <wojtek@puchar.net>,
 freebsd-hackers Hackers <freebsd-hackers@freebsd.org>,
 Rebecca Cran <rebecca@bluestop.org>, Mark Johnston <markj@freebsd.org>
Subject: Re: 13-CURRENT: several GB swap being used despite plenty of free RAM
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why someone changes WELL WORKING swapping algorithm?

On Sun, 18 Nov 2018, Stefan Blachmann wrote:

> So I guess the unwillingness of the developer team to add an option
> like "NoPreemptiveSwapping", which disables swapping out as long as
> there is free physical memory available, is of psychological nature.

in FReeBSD 12 there is

vm.swap_idle_threshold2: 10
vm.swap_idle_threshold1: 2
vm.swap_idle_enabled: 0


which works as expected and can be turned on or off as required.

what's wrong with it