From owner-freebsd-questions@freebsd.org  Tue Aug 25 16:02:38 2015
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Date: Tue, 25 Aug 2015 09:02:35 -0700
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Subject: Re: How to minimize the number of writes to CF card?
From: Michael Sierchio <kudzu@tenebras.com>
To: FreeBSD Questions <freebsd-questions@freebsd.org>
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On Tue, Aug 25, 2015 at 3:13 AM, Matthew Seaman <matthew@freebsd.org> wrote:

> On 2015/08/25 10:58, zhup wrote:
>
> > I am going to install Freebsd on CF card and my question is:
> > how to minimize the number of writes to CF card?
>
> Mount it read-only?
>

I could have offered that advice without being facetious, Matthew. ;-)

If you have adequate RAM and can mount a mfs for /var, symlink
/tmp->/var/tmp, that works. I have some rc scripts that periodically mount
a partition r/w and save the state of things in /var that I want to
persist.

And if you can't mount it read-only, mount it rw,noatime. Updating access
time causes many, many writes.

- M