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Subject: Re: swapfile query
From: David Chisnall <theraven@FreeBSD.org>
In-Reply-To: <201708191654.v7JGs8sM063853@slippy.cwsent.com>
Date: Sat, 19 Aug 2017 18:03:01 +0100
Cc: tech-lists <tech-lists@zyxst.net>, freebsd-current@freebsd.org
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References: <201708191654.v7JGs8sM063853@slippy.cwsent.com>
To: Cy Schubert <Cy.Schubert@komquats.com>
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On 19 Aug 2017, at 17:54, Cy Schubert <Cy.Schubert@komquats.com> wrote:
>=20
>> 3. should total swap be 1x 2x or some other multiple of RAM these =
days?
>=20
> Depends. If you're running some kind of database server or OLTP=20
> application. Some vendors recommend no swap whatsoever while others=20
> recommend some. What does your application vendor recommend?

The main advantage of swap these days (on machines with that sort of =
amount of RAM) is to allow you to keep some file-backed memory objects =
in memory in preference to leaked (or very cold) heap memory. =20

David