On Feb 6, Jukka Marin wrote
> Trying to benefit from the atactl program and disk sleep mode on my
> laptop, I mounted / with "nodevmtime" and "noatime" and /usr and /var
> with "noatime".  I then set the disk standby-timer to 5 seconds and
> the disk stops after 5 seconds of inactivity, just as expected.
> 
> However, the disk starts again every 30 seconds - thanks to update.
> 
> Why? :-)

I think sync(2) will always update the timestamp of the superblock.
I have in mind to move update to a kernel thread to solve this problem
(and a few others).

> 
> Sure, cron writes to /var/cron/log every 10 minutes by default (and
> cron has no options at all, so this can't even be disabled). 

It does this because is starts atrun every 10mn. If you kill /usr/libexec/atrun
from your crontab, the log file should be updated less often.

--
Manuel Bouyer <bouyer@antioche.eu.org>
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