In case you found performance issues with java applet execution after updating Java to 8u60 or 8u65.
Frontend service methods like, up/download, execute of files, file open dialog and etc., might be affected.
To be more specific, I post an example here for your reference.
Execute a table (E.G., T000) in T-cd:se16 with “ALV Grid display”.
Then select “spreadsheet” > “Excel (in Office 2007 XLSX Format)” to export the file,
This is a known bug in java, see following SAP Note for more details.
Current workaround is to use Java version <= 8u51.