Date: Tue, 21 Nov 2023 21:36:31 -0500
From: Bruce Momjian <bruce@momjian.us>
To: Thomas Munro <thomas.munro@gmail.com>
Cc: John Ekins <jrekins@gmail.com>,
	Peter Eisentraut <peter.eisentraut@2ndquadrant.com>,
	pgsql-docs@postgresql.org
Subject: Re: [DOCS] The reference to 'atacontrol' on FreeBSD is outdated.
Message-ID: <ZV1pL9R2keCJUXfb@momjian.us>
References: <20170808224017.8424.69170@wrigleys.postgresql.org>
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On Wed, Nov 22, 2023 at 03:25:07PM +1300, Thomas Munro wrote:
> On Wed, Nov 22, 2023 at 2:12 PM Bruce Momjian <bruce@momjian.us> wrote:
> > On Sat, Aug 12, 2017 at 10:47:00PM +0100, John Ekins wrote:
> > > Sure. Camcontrol does indeed cover IDE, SCSI and SAS drives.
> > >
> > > Replace this line:
> > > On FreeBSD, IDE drives can be queried using atacontrol...
> > >
> > > With this:
> > > On FreeBSD, IDE drives can be queried using camcontrol identify...
> > >
> > > In other words, the query is the same as for SCSI drives. For verification this
> > > is what the output looks like:
> > >
> > > root@bsd11desk:/home/jre # camcontrol identify 0:0:0 | egrep "Feature|write
> > > cache"
> > > Feature                      Support  Enabled   Value           Vendor
> > > write cache                    yes yes
> > >
> > > I appreciate the Postgresql docs are not meant to be FreeBSD tutorials.
> >
> > I know this email is six years old, but I have applied this fix to all
> > supported Postgres versions.  A huge apology for this delay.
> 
> It's funny that we discuss IDE drives at all.  They stopped being
> manufactured a decade ago and are not supported by modern chipsets or
> boards etc[1].  I've been meaning to do something about that, but I
> didn't have enough round tuits to research what to write about current
> storage technologies...  but also in the case of FreeBSD, it doesn't
> let you turn the write cache on and off with nvmecontrol yet, but
> someone has a relevant patch out (D32700) so I was also waiting for
> that to go somewhere before writing in...

I don't think it is safe to disable the nvme cache since it is a cache
and a staging area.  If you turn it off, it will burn out the chips over
time.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EDB                                      https://enterprisedb.com

  Only you can decide what is important to you.