Thanks to feedback from several readers, we now know
that Mac OS X 10.5 "Leopard" will run the routine maintenance cron jobs
after startup or waking up if the computer was off or asleep when they
were scheduled. Earlier versions of Mac OS X do not do this.
OS X System Maintenance Routines
From Jeff:
It's easily verified that the daily, weekly, and monthly cron
scripts will run at the first available time slot if they miss their
overnight executing times by opening "Console.app" from
/Applications/Utilities and looking at the entries for "daily.out,"
"weekly.out," and "monthly.out" under "/Library/Logs." (UPDATE: The
logs may sometimes be found in "/var/log" instead. ed)
My system sleeps overnight, and it's easy to see that all three of
these cron scripts are executed sometime between 6 a.m. and 8 a.m.
(about the time I get up and wake up the computer), and, therefore,
there is no need to "force" these scripts to run manually.
Jeff
Hi Jeff,
Well, that clears that up. I don't get into the
Console a whole lot.
Charles
Cron Jobs Run on Wakeup or Startup
From Ian:
"I have heard, but haven't been able to confirm as
yet, that recent versions of OS X have been configured to run the
cron jobs at a different time if the computer was asleep or off during
the regular scheduled time."
That seems to be the case in 10.5.4. The "daily" script ran a little
after nine when I fired up my 'Book this morning.
Thanks, Ian.
Charles
Running OS X System Maintenance Routines
From David:
Hi Charles,
You asked for info re. system maintenance. This is what I know.
According to
this article at Macworld, if your computer is asleep at night,
"Leopard is smart enough to run the missed scripts the next time you
wake up your computer. (Tiger is supposed to do so, as well, although
this automatic feature didn't work as well.)"
The Macworld article is dated June 2, 2008, but Apple has this support
document, last modified July 18, 2008, which says "Mac OS X
performs background maintenance tasks at certain times if the computer
is not in sleep mode. If your computer is shut down or in sleep at the
designated times, the maintenance does not occur." The document says
Mac OS X 10.5 is one of the Products Affected.
We're through the looking glass here, Mac users.
Take care,
Dave Lillo
Hi Dave,
See Jeff's note above, which would appear to verify
what Macworld said.
Charles
Using Anacron to Run Routine Maintenance
From Nancy:
Dear Charles,
I enjoyed your article in Miscellaneous Ramblings about the value of
running routine maintenance utilities, and I plan to forward it to
friends who are new to the Mac.
I use Onyx as well, but wondered if you were familiar with Anacron.
It is a freeware application that runs the three cron scripts in the
background whenever your computer is awake, without having to remember
to launch Onyx and trigger the scripts manually. It runs under both
Leopard and Tiger, and earlier versions are available for Jaguar and
Panther as well. I have used it for a couple of years now with no
problems.
Best,
Nancy
Hi Nancy,
I hadn't heard of that utility.
Sounds handy, although I guess Leopard does that now
automatically without any third-party help.
I notice that the Anacron site has posted a notice
reading:
"Note: This version of Anacron will run on MacOS
10.5 (Leopard) but it is not needed, as the Leopard launchd will run
skipped jobs when the machine is next awake."
Charles
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