Ok I think I had a too much aggressive custom logging system (a page frequently saved) and my xwiki encoutered this bug. http://jira.xwiki.org/browse/XWIKI-13336?focusedCommentId=91972&page=co… I think it is ok now (except I still wonder <<   I wonder, Is there a timeout associated to the script that   runs and is there feedback in the event of an error (or a   way to activate logs for job scheduled)?>>     Thxs     Pascal BASTIEN