[ale] Ubuntu Linux Defrag EXT4

[Paul Cartwright]

On Mon September 13 2010, Ed Cashin wrote:
> The read-only check shouldn't be dangerous (although googling
> revealed one claimed case where they were prompted and answered
> "Yes", resulting in corruption), but it might be confusing.  I suspect
> that running "sync" during a period of relative inactivity would reduce
> the discrepancy between the metadata on disk and the stuff in RAM.

the command that was given ran by itself, unattended, and did not ask, just 
reported. FOR SURE I would have answeed NO, on a mounted filesystem!!
I used to bring down UNIX systems in less than 2 seconds by running this 
script:
while true
do
sync
sync
sync
uadmin 2 0
done

so it would sync 3 times and literally shut off like a lightswitch was thrown.
Normally I only did that on sick systems where I was shutting it down for 
severe maintenance :)
don't try that at home!

-- 
Paul Cartwright
Registered Linux user # 367800
Registered Ubuntu User #12459
http://usdebtclock.org/