svn commit: r324681 - in head/etc: defaults periodic/daily

[Alan Somers]

This change defeats the anticongestion mechanism.  If
daily_ntpd_leapfile_background is set and 480.leapfile-ntpd runs
before any other periodic script that uses anticongestion (like
/usr/local/etc/periodic/security/410.pkg-audit), then the
anticongestion mechanism will effectively be disabled for those later
scripts.

It's worth asking why you would want to do this in the background
anyway.  Does the submitter complain that it was too slow?  The entire
point of anticongestion is to slow it down.  If the submitter didn't
like that, he could've set anticongestion_sleeptime=0 to disable it
entirely.  Or was the problem that the "service ntpd onefetch" is too
slow, even after the anticongestion timer ran?  I doubt it, but if so
then you should background just that part instead of backgrounding
anticongestion too.

-Alan

On Mon, Oct 16, 2017 at 7:15 PM, Cy Schubert <cy at freebsd.org> wrote:
> Author: cy
> Date: Tue Oct 17 01:15:13 2017
> New Revision: 324681
> URL: https://svnweb.freebsd.org/changeset/base/324681
>
> Log:
>   Provide an option to run the anticongestion ntpd leapfile fetch in
>   the background.
>
>   Original patch submitted by feld at . I added the "optional" bit.
>
>   Submitted by: feld (original patch)
>   MFC after:    2 weeks
>
> Modified:
>   head/etc/defaults/periodic.conf
>   head/etc/periodic/daily/480.leapfile-ntpd
>
> Modified: head/etc/defaults/periodic.conf
> ==============================================================================
> --- head/etc/defaults/periodic.conf     Tue Oct 17 01:12:17 2017        (r324680)
> +++ head/etc/defaults/periodic.conf     Tue Oct 17 01:15:13 2017        (r324681)
> @@ -141,6 +141,8 @@ daily_status_mail_rejects_shorten="NO"                      # Shorten out
>
>  # 480.leapfile-ntpd
>  daily_ntpd_leapfile_enable="YES"                       # Fetch NTP leapfile
> +daily_ntpd_leapfile_background="NO"                    # Fetch NTP leapfile
> +                                                       # in the background
>
>  # 480.status-ntpd
>  daily_status_ntpd_enable="NO"                          # Check NTP status
>
> Modified: head/etc/periodic/daily/480.leapfile-ntpd
> ==============================================================================
> --- head/etc/periodic/daily/480.leapfile-ntpd   Tue Oct 17 01:12:17 2017        (r324680)
> +++ head/etc/periodic/daily/480.leapfile-ntpd   Tue Oct 17 01:15:13 2017        (r324681)
> @@ -13,8 +13,15 @@ fi
>
>  case "$daily_ntpd_leapfile_enable" in
>      [Yy][Ee][Ss])
> -        anticongestion
> -        service ntpd onefetch
> +       case "$daily_ntpd_leapfile_background" in
> +       [Yy][Ee][Ss])
> +           (anticongestion && service ntpd onefetch) &
> +           ;;
> +       *)
> +           anticongestion
> +           service ntpd onefetch
> +           ;;
> +       esac
>          ;;
>  esac
>
>