Private Server - logs not generated after 17w15a snapshot

It seems this snapshot doesn't create log files for my private server.
I've got log files for 17w14a, but nothing since the 8th of April (I updated on the 14th of april to 17w15a, but the server hadn't been up for the week between)

Command line to run the server is:
"C:\ProgramData\Oracle\Java\javapath\java.exe" -Xmx4G -Xmn2048M -jar "C:\Users\Anthony\AppData\Roaming\.minecraft\Server\minecraft_server.17w15a.jar" nogui

The -xmn switch used to be 1024, but 17w15a hit 2GB within 20 seconds of loading a world. 1024 had the same problem.