Solution : https://service.sap.com/sap/support/notes/1523781 (SAP Service marketplace login required)
Key words :
connection pool uwlpool_<alias>$<connectortype>, connection pool uwlpool_<aliasname>$<connectortype>, current pool size limit, r3systeminfo#plain###problem occurred, empty work item list, uwl manage attachments ui, opening uwl administration page, inappropriate warning message appears, uwl work item, uwl delta pull
Related Notes :
1133821 | UWL Destination Service configuration |