This is most noticeable when traveling with mobs or on a mob. Wolf pack stalls, riding horse causes no movement available every 30s.
Without GUI. My java executable is running with these params:
john 14477 3.5 19.4 6119080 1623304 ?? S 29Oct13 1438:33.29 /usr/bin/java -Xmx3072M -Xms1024M -jar /Users/john/Minecraft/server/minecraft_server.jar nogui
Yes, this is still an issue in server 1.7.9. Quad core i7 Mac Mini "cannot keep up" frequently according to server logs. I don't know if the CPU still gets pegged, I've mostly stopped playing.