When the 720 kernel is used the default syslog record length will be 320 bytes. When the 720 kernel is used on a ABAP system for which still the central system log daemons rslgsend and rslgcoll are needed, the instance profile parameter rslg/new_layout value must be set to 9 (notes: #1517379, #1118986, #1633731, #1453912 and #1636252).
If a system is upgraded and there are still old records with the old length in the syslog files on disk, the administrator should delete all the old syslog files before the upgraded system is started again. When the users still complains about corrupted syslog entries after the upgrade and after deleting the old existing syslog files, the administrator needs to set the instance profile parameter rslg/new_layout value to 9, stop the system and delete all the old syslog files again for each instance and restart the system again.
Always be sure that you did delete the old syslog files in the correct way.