Freeze to stop responding

[JmAbuDabi]

Ubuntu does not start right away 18.04. Having passed the Grub menu, the system starts up and then a black screen. Reboot, so maybe several times. Hard drives: Smart OK.

How to boot I enter the password. Run Chrome. looking through YouTube. Hangs tightly. The mouse does not move. I hear the last sound from the video, on repeat.

Before that, I started the Java game. It occupies almost all the operational memory. It needs at least 4Gb, I have 6Gb. In one moment freeze and not responding Ubuntu 18.04.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: gnome-shell 3.28.3-0ubuntu0.18.04.2
ProcVersionSignature: Ubuntu 4.15.0-36.39-generic 4.15.18
Uname: Linux 4.15.0-36-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.4
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Wed Oct 24 23:26:29 2018
DisplayManager: lightdm
GsettingsChanges:
 b'org.gnome.shell' b'favorite-apps' redacted by apport
 b'org.gnome.desktop.interface' b'gtk-im-module' b"'gtk-im-context-simple'"
InstallationDate: Installed on 2018-10-16 (8 days ago)
InstallationMedia: Ubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725)
SourcePackage: gnome-shell
UpgradeStatus: No upgrade log present (probably fresh install)

[Daniel van Vugt (vanvugt)]

Please:

1. Reproduce the freeze, and then reboot.

2. Next time you can reboot successfully run this command to collect the log from the previous frozen boot:

   journalctl -b-1 > previous_boot.txt

and then send us the file previous_boot.txt.

[JmAbuDabi (dambldor91)]

I started Java game and freeze. Mouse and Key board not responds.

Alt+SysReq REISUB not working.

[JmAbuDabi (dambldor91)]

loading occurred for the third time.

Freeze occured in Unity environment.

I think that the gnome-shell has nothing to do with my problem

[Daniel van Vugt (vanvugt)]

It sounds like you're reporting two problems:

 * Slow to boot with black screen

 * Desktop freeze with the mouse not moving

And it sounds like you want to focus on the second issue..

Please reboot, open a Terminal window and run:

   free -m

Now please tell us what it shows immediately on login before you have run any apps, and what it shows after starting the Java game.

Please also follow these instructions in case something is crashing:
https://wiki.ubuntu.com/Bugs/Responses#Missing_a_crash_report_or_having_a_.crash_attachment

[Launchpad Janitor (janitor)]

[Expired for gnome-shell (Ubuntu) because there has been no activity for 60 days.]