January 12, 2021

[Note] GNOME shell gets slower

System: Ubuntu 20.04

GNOME gets slower as I leave the computer on for more than a few days and keep using it -- drop down menu gets affected especially slow.  Seems like some menus are ok though.  And overall computer performance gets slower also.

Login out-back in makes little better, but not so much.  Eventually GUI becomes unusable and have to restart.

I did some googling and seems it is a known issue but happens to others in different situations.

There is no fix for this yet.  

If that happens, the remedy is restarting gnome-shell.  

ALT-F2 and then type "r".






[Note] Set CPU to max for Ubuntu 20.04

Objetive: Set CPU speed to max


Setting CPU performance is not working properly in Ubuntu 20.04 for old Xeon (max 3GHz).  Trying to set it to MAX all the time.


Checking current setting:

$ more /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor


Changing setting manually:

$ sudo -i
$ echo "performance" | sudo tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor

However, this setting will revert after reboot.

Step 1. Changing in BIOS

For my PC (Dell workstation), SpeedStep can be disabled in BIOS.

After reboot, the CPU speed still fluctuate.

Step 2. change boot option in grub

$ sudo vi /etc/default/grub

GRUB_CMDLINE_LINUX_DEFAULT="intel_idle.max_cstate=0 processor.max_cstate=1 pcie_aspm=off quiet splash"

Step 3. disable 'ondemand'

$ systemctl is-enabled ondemand
$ systemctl disable ondemand

and reboot.


January 11, 2021

[Note] sonatype-nexus in Docker


1. Create data folder

$ mkdir /data/docker.data/nexus && chown -R 200 /data/docker.data/nexus

2. Map the data folder and create container

$ docker run -d -p 8088:8081 --name nexus -v /data/docker.data/nexus:/nexus-data sonatype/nexus3

Wait about 3 min.  


Set up Nexus

1. admin password is in <data folder>/nexus/admin.password

$ more /data/docker.data/nexus/admin.password 

2. Open http://localhost:8088, ID=admin and PW=from previous step

3. Update password, create user, create repository.


Set up .m2/settings.xml:

      <password>*USER PASSOWRD SET IN NEXUS*</password>

Deploy JAR.  "repositoryId=" must match with server id from above settings.xml:

$ mvn deploy:deploy-file \
    -DgroupId=com.keithkim.test \
    -DartifactId=test-module \
    -Dversion=1.0.0 \
    -DgeneratePom=true \
    -Dpackaging=jar \
    -DrepositoryId=test \
    -Durl=http://localhost:8088/repository/keithkim/jars \

If you get build failure like this:

[INFO] ------------------------------------------------------------------------
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  1.163 s
[INFO] Finished at: 2021-01-11T01:53:52-05:00
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-deploy-plugin:2.7:deploy-file (default-cli) on project standalone-pom: Failed to deploy metadata: Could not transfer metadata com.keithkim.test:test-module/maven-metadata.xml from/to test (http://localhost:8088/repository/keithkim/jars): Transfer failed for http://localhost:8088/repository/keithkim/jars/com/keithkim/test/test-module/maven-metadata.xml 400 Bad Request -> [Help 1]

Edit this file, <DATA DIR>/etc/nexus.properties

$ vi /data/docker.data/nexus/etc/nexus.properties

Add this line:


Restart the container and try again.