Hello Jan, ----- Original Message ----- > From: Jan Kaluža <jkaluza@xxxxxxxxxx> > Subject: Re: logrotate(8) and copytruncate as default > > I'm not sure right now if the benefits of the "copytruncate" usage are > strong enough in comparison with the possibility to lost the messages > during rotation. I did a small experiment to test how much data loss would incur in copy-truncate. First command constantly writes to a file. While the second one uses an exclusive lock to temporarily halt the write operation, do a copy, truncate and release the exclusive lock so that the write continues where it was stopped. === $ cd /tmp/exp/ # Following command continuously writes to a file. # $ (count=0; while(true); do count=`expr $count + 1`; \ echo `date "+%d %a %Y %T"` $count; done >> test.log &) # Following command uses exclusive lock to halt the write # operation, perform copy-truncate, and release the lock. # $ flock -x test.log -c 'cp test.log test.log.1; > test.log' $ $ $ tail -n -4 test.log.1 27 Thu 2013 21:14:14 7317 27 Thu 2013 21:14:14 7318 27 Thu 2013 21:14:14 7319 27 Thu 2013 21:14:14 7320 $ head -n 4 test.log 27 Thu 2013 21:14:14 7321 27 Thu 2013 21:14:14 7322 27 Thu 2013 21:14:14 7323 27 Thu 2013 21:14:14 7324 === As can be seen above, there does not seem to be any data loss at all. Thank you. --- Regards -Prasad http://feedmug.com -- devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/devel
