There is a bug that occurs when we disable the value storage (which seems to be the case in GateIn 3.5/ JPP 6.0 by default), in that particular case we realized that the swap files were not properly cleaned up. More details here https://jira.exoplatform.org/browse/JCR-2053. The bug will be fixed in 1.15.2 and 1.14.11. The bug fix consists in purging the swap files at runtime but also at startup time so it is important to make sure that your cluster config doesn't make the swap directory being shared between the cluster nodes otherwise you could face some issues at startup. This BZ is for tracking purpose and a need of Release note for JPP 6.0 GA, issue will be fixed by upgrading JCR to 1.15.2 and higher.
This needs CCFR if it is going to be included in the Release Notes for 6.0
Fixed in eXo JCR 1.15.2 - subject for testing.
Fixed in JPP 6.1.0