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From: "John Levine" <johnl@iecc.com>
To: freebsd-questions@freebsd.org
Cc: jude.obscure@yandex.com
Subject: Re: Swap on SSD
In-Reply-To: <d84a4c7e-f311-3d13-2d18-d15348420ee4@yandex.com>
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In article <d84a4c7e-f311-3d13-2d18-d15348420ee4@yandex.com> you write:
>On 02/04/18 16:49, @lbutlr wrote:
>> I have a machine that has dual SSDs in it and no spinning disks. FreeBSD has a 4GB (or so) swap partition that it created on the installation of FreeBSD 11.1.
>> 
>> Isn't this going to cause problems for the SSD to have swap constantly working the drive?

In my experience FreeBSD hardly swaps at all unless it's horribly
overloaded.  Remember that the only page frames that get written to
swap are ones that don't have a home somewhere else.  A large amount
of any process image is program and data mapped in from disk files,
and they don't get swapped, they just get deleted from memory and
reloaded from the disk if needed.

Do a "systat -vm" and you'll see how much swapping your system is doing.