I have an application which includes Derby which have been working fine, both on Windows and on Mac.
When I upgrade my Mac to Sierra it still was no problem but I had some users complaining that after upgrade to Sierra the application was very slow.
Yesterday I went out and when I came back I had the same problem (not sure but I might reboot my system before I went out).
I run profiler in NetBeans and suddenly everything was fine but when I run it as normal Derby calls is at least 10 times slower.
I have tried adding my computer to hosts described here but it didn´t improve performance.