Logs reported in that part of diskusage is direct syslog messages sent, so it won't account for what's actually stored in the LEM database (i.e. all the other stuff sent from agents and indirect logging). The archive that Pradeep refers to is the actual database storage, so that would tell you what your true event storage looks like. This is the "Data" part of Logs/Data (the other 122G of your 123G).
You might also want to check out the Database Maintenance Report on the reports side, there's a couple of related reports there that do try to break down your events and database growth. That might help paint a different picture.