From mboxrd@z Thu Jan  1 00:00:00 1970
From: krewat@kilonet.net (Arthur Krewat)
Date: Mon, 4 Dec 2017 19:58:54 -0500
Subject: [TUHS] signals and blocked in I/O
In-Reply-To: <alpine.BSF.2.21.1712051104390.99186@aneurin.horsfall.org>
References: <CAEoi9W5mFaQjuGAqSQZSusuyj2uyUX4PvsKVq8bOuM5219E1tQ@mail.gmail.com>
 <CAC20D2NcnW1YHdd5+3Y8yQqghGeLMvy8urDV7R5GevcLpizLew@mail.gmail.com>
 <20171201161810.GM3924@mcvoy.com>
 <CANCZdfpYWbLdkx4fNURFnLM5VGt+qDcnnMyHQ+M4iwAziS2a9A@mail.gmail.com>
 <20171201172603.GO3924@mcvoy.com>
 <BADECBD9-D2B4-4788-8308-87EBF93D555A@bitblocks.com>
 <20171201223859.GX3924@mcvoy.com>
 <20171201230302.0DC351FA41@orac.inputplus.co.uk>
 <20171201230934.GA24335@mcvoy.com>
 <20171201234230.F33D4156E523@mail.bitblocks.com>
 <20171202004850.GB24335@mcvoy.com>
 <201712041636.vB4GaFEp017803@freefriends.org>
 <alpine.BSF.2.21.1712050905250.99186@aneurin.horsfall.org>
 <01db01d36d52$cffe9430$6ffbbc90$@ronnatalie.com>
 <CANCZdfozzp3G0R+7+2KEmNnvRTmwNN67GjOKHTv-ORT2usR8qw@mail.gmail.com>
 <alpine.BSF.2.21.1712051104390.99186@aneurin.horsfall.org>
Message-ID: <7c7b34b5-0a5c-3080-6cd0-ff451c2f162d@kilonet.net>

On 12/4/2017 7:49 PM, Dave Horsfall wrote:
> On Mon, 4 Dec 2017, Warner Losh wrote:
>
> [ Swap files ]
>
>> Pages are pages. The filesystem handles the details for the offset of 
>> each one. There's no contiguous on disk requirement.
>
> I've used at least one *ix OS that required it be both contiguous and 
> pre-allocated; Slowaris?
>
Nope, unless mkfile is is guaranteed to give you contiguous space:

# uname -a
SunOS vmsol8 5.8 Generic_108529-05 i86pc i386 i86pc
# mkfile 100m a.a
# swap -a /a.a
# swap -l
swapfile             dev  swaplo blocks   free
/dev/dsk/c0d0s1     102,1       8 1048936 1048896
/a.a                  -        8 204792 204792