Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 10 Jan 2024 13:28:16 -0800
From:      Rick Macklem <rick.macklem@gmail.com>
To:        "Lyndon Nerenberg (VE7TFX/VE6BBM)" <lyndon@orthanc.ca>
Cc:        Olivier Certner <olce@freebsd.org>, freebsd-current@freebsd.org
Subject:   Re: noatime on ufs2
Message-ID:  <CAM5tNy4HuHb=GpQXvE4h2NC8_azOwDS3H7wY3UK%2BcE07owPr3A@mail.gmail.com>
In-Reply-To: <a5e38bfbabd37084@orthanc.ca>
References:  <ZZqmmM-6f606bLJx@int21h> <CAGMYy3vsSD7HHtGxYXJn%2Busr8GCOd-0Xe1crs-Nx=qw-bYJ6HA@mail.gmail.com> <2eabfb91-afc3-47f7-98b9-1a1791ae6e7d@app.fastmail.com> <6714298.qJWK8QVVMX@ravel> <a5e38bfbabd37084@orthanc.ca>

next in thread | previous in thread | raw e-mail | index | archive | help
On Wed, Jan 10, 2024 at 12:44=E2=80=AFPM Lyndon Nerenberg (VE7TFX/VE6BBM)
<lyndon@orthanc.ca> wrote:
>
> Olivier Certner writes:
>
> > I've never found any compelling reason in most uses to enable "atime", =
except
> >  perhaps local mail but as addressed in other answers it is a relic of =
the pa
> > st mostly irrelevant today.  And its drawbacks are well known and can b=
e seri
> > ous.
>
> When UNIX ran on PDP-11s and disk pack sizes were measured in the
> tens of megabytes, atime was very helpful in determining which files
> were likely candidates for archiving to tape when the disk was
> getting full.  And in the Usenet days it was common to mount
> /var/spool/news noatime, which eliminated a *lot* of meta-info
> write traffic.
>
> These days, other than /var/mail, I can't think of a compelling use
> for it.  I've been running my Plan 9 systems with atime disabled
> ever since fossil arrived (decades) without any impact.
>
> I don't see any issue with making noatime the default.  For those
> that must have it, /var/mail can be carved out as a distinct
> filesystem and mounted appropriately.
Just choosing the last message in the thread...
I do not have a strong opinion w.r.t. atime, but I do believe that
changing the default would be a POLA violation.

Please look at this email thread, where the opinion w.r.t. atime
seemed quite different:
freebsd-hackers@ Oct. 5, 2023
Subject:  copy_file_range() doesn't update the atime of an empty file

I'd put a url here, but gmail always puts the subject line in here when
I copy/paste the url?

Basically I did not think that updating the infd's atime when copy_file_ran=
ge()
did not actually copy any data, but the collective disagreed, so I patched
the NFSv4 client. (I do not know if markj@'s patch did get committed).
They also collectively thought that Linux did a poor job w.r.t. atime.

rick

>
> --lyndon
>



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAM5tNy4HuHb=GpQXvE4h2NC8_azOwDS3H7wY3UK%2BcE07owPr3A>