Red Hat Bugzilla – Bug 44665
Be kind to laptop users -- don't write to drive all the time
Last modified: 2007-04-18 12:33:42 EDT
Hard drives use a lot of power, which is an issue on laptops. RedHat 7.1
is not ideal on laptops -- the drive never gets a chance to spin down for
very long. Something writes to the disk. I've fixed this on my system,
and suggest RedHat does the same by default.
I suggest that RH make two small modifications for a "laptop" install. The
first is in /etc/syslog,
The logs you lose are not of any great value. Anyone who needs
confirmation that cron has woken up can get it another way.
See also bug 44666
Um, vixie-cron never uses WARN messages, if I'm reading the source right. So,
are you suggesting that we dump *all* cron messages?
No. I'm only suggesting that a single message be dumped, or maybe two.
Take an idle machine, and tail /var/log/cron. You'll see a mind-numbing
list of thousands of identical entries:
Sep 17 17:10:00 hardhat CROND: (root) CMD ( /sbin/rmmod -as)
Sep 17 17:20:00 hardhat CROND: (root) CMD ( /sbin/rmmod -as)
Sep 17 17:30:00 hardhat CROND: (root) CMD ( /sbin/rmmod -as)
Sep 17 17:40:00 hardhat CROND: (root) CMD ( /sbin/rmmod -as)
Sep 17 17:50:01 hardhat CROND: (root) CMD ( /sbin/rmmod -as)
Sep 17 18:00:00 hardhat CROND: (root) CMD ( /sbin/rmmod -as)
Sep 17 18:01:00 hardhat CROND: (root) CMD (run-parts
Dump the periodic messages. Leave any errors or true warnings.
Let the laptop (or desktop) go to sleep.
This is the only periodically written log I found.
The modutils cron entry isn't there in 7.2, FWIW.
Try setting a laptop (or desktop) to spin down the hard drive:
hdparm -S5 /dev/hda
And see how long it stays spun down
Still present as of RH 7.3
It seems that RedHat has compiled cron NOT to use syslogd at all! Is
there any way to get RedHat cron not to log?
Do you mean you would prefer it to use syslogd?
> Is there any way to get RedHat cron not to log?
It is a build option.
vixie-cron-4.1-+ always logs with syslogd
(by default, this is directed to /var/log/cron).
You can disable cron.* in /etc/syslog - you'll
need also to disable the auth.info messages
generated from PAM for each cron job.
You could also disable logging completely
(don't run syslogd).
These are local configuration choices you can make -
the default configuration does not need to change.