I've updated android studio from 3.0 to 3.0.1 but when I launch Emulator it didn't get launched and gives message in event log:
Emulator: Process finished with exit code 0
I restarted Android Studio and create a new device in AVD MANAGER then I have increased the RAM size of emulator and it works nicely.
UPDATED Sometimes it happens when you close emulator during building the App in to emulator.