how are you starting the Server ?
Latest Launcher or the old one or through batch file ?
this is your startup
[2016-12-20 00:01:19] [JVM-ARGUMENTS] [-Xms512m, -Xmx1024m, -Xincgc, -Xshare
ff]
this is the one from my work PC
[2016-12-21 12:58:50] [JVM-ARGUMENTS] [-Djava.net.preferIPv4Stack=true, -Xmn128M, -Xms512M, -Xmx2048M, -Xincgc]
please try at least increasing the -Xmx value to 2gb (if memory is available)
or try it with all of those parameters.