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Date: Thu, 08 Feb 2018 17:49:06 +0000
From: Frank Leonhardt <frank2@fjl.co.uk>
To: freebsd-questions@freebsd.org
Subject: Re: Swap on SSD
Organization: FJL Microsystems
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On 2018-02-07 19:38, Christian Weisgerber wrote:
> On 2018-02-07, Frank Leonhardt <frank2@fjl.co.uk> wrote:
> 
>> There seems to be some confusion on this list about swapping and 
>> paging.
>> Swapping is old hat. Basically when doing a context swap you wrote a
>> non-running process to a swap area to free up RAM space. We don't do
>> that anymore - we use demand paged virtual memory.
> 
> Demand paging was introduced in UNIX 32V and entered the BSD line
> with 3BSD.  That's around 1978-80, so almost forty years ago.

Yeah, but not everyone could afford an MMU until much later :-)

Did you ever run the UCSD P System? For some reason the keyboard driver 
got swapped out (on to 8" Floppy) and every time you hit the keyboard 
the drive went <CLUNK>.