Overview:
launching yast2 system log in KDE when /var/log/messages is large (tested w/
1.2gb file) thrashes the I/O endlessly, locking up the system.


Steps to Reproduce:
1) create a large /var/log/messages, preferrably 1.2GB
2) launch System Log in YaST2 using KDE


Actual Results:
Hard drive activity (I/0) goes to maximum (thrashes), locking up the system.
After 36 minutes, unable to even kill the process due to locking, I turned off
the power.


Expected Results:
/va/log/messages should be viewable in System Log. System Log should not lock
I/O when reading log file. See Additional Information regarding vim below.


Fix:
Rotate log, creating a fresh tiny log file. Now YaST2 System Log opens without
issue.


Additional Information:
Possible causes of trashing, besides badly written code not taking into
consideration filesize, may be due to 1) being launched by root and 2) having a
(too high) nice level. 

Opening the 1.2GB file in vim took 4 seconds, no locking up the system and I
was able to navigate the file without problems. This is vim with highlighting
and lots of addons enabled, so it's possible.

The 1.2GB /var/log/messages log file was properly formed, not faked or having
bad syntax, due to another 13.2 bug where log rotate was not on by default
after upgrading 13.1 -> 13.2.