Why qemu-system-x86_64 (android emulator) is still running

Question

I am using android studio with VM. After running some emulators I noticed that I still have a process named qemu-system-x86_64 running which occupies 1.9GB of my RAM (I am running the emulator with software support only).

I know that the emulator after invoked it's independent of android studio so that make sense up to a level but I am not running any emulator now.
I checked this answer to see if I can shutdown my emulator but I don't have any VM appearing:

virsh list

Also, running:

ps aux | grep qemu-system-x86

gorfani+ 10055 0.0 12.6 6988716 2055984 ? Sl Oct09 0:30 /home/gorfanidis/Android/Sdk/emulator/qemu/linux-x86_64/qemu-system-x86_64 -netdelay none -netspeed full -avd Pixel_2_API_28

reveals that I was using Pixel_2_API_28.

I want to run an emulator with different API so the previous one should be shutdown.

So, a few question arise:

• Why the process is still running while I don't see any emulator running. Is this a hung emulator or something? If it's just the already saved-state emulator shouldn't this release it's resources?
• Is it safe to kill this process? Would it harm my emulator? I know it's no big deal and could reinstall the emulator but sometimes it's convenient to continue where I left last time.
• How should I deal with VM of this kind. Shouldn't virsh reveal something or am I mixing things up here?

Answer 1

You can kill a specific process by process id with -9 parameter for killing process tree also, Or You can close these process by the following command

sudo killall qemu-system-x86*