Have you applied HotFix KA357831? We had DSO issues in our CLM 2.1 SP1 but we are on a Windows platform, therefore may not apply to you.
Environment : CLM 2.1 , CLM 2.1 SP1
Atrium Core : 7.6.04 SP2
Reconciliation job stopped intermittently with no helpful hints in logs.
Apply this fix for Enterprise/ITSM AR Server as well as Cloud-AR Server
For instrcutions , check the readme.txt available in the attached rar file.