journalctl _PID=<pid number>
To obtain PID number when you have the process name [or part of the process name], use the following:
ps aux | grep -i <process name>
The manual page only refers to it in examples. A commonly used slicing option is to see logs of current boot only. This can be done as follows.
Another option is to look at logs of a particular unit only. This can be done in the following way.
journalctl -u <unit name>
The unit name could be some daemon name like '
mysqld'. Unfortunately, this does not work with '
kernel' as a unit. It can be combined with the
-boption though. However, I find myself dealing with messages from various units. So, I scan through all messages and find the messages I need. To filter them out, I can use time stamps in the messages using the following format.
journalctl --since='2013-03-06 22:58:34' --until='2013-03-06 23:00:34'
The beginning time stamp works fine; but the ending time stamp does not work. I talked about it at #systemd IRC channel. It is fixed and will be released soon.