tar: Archives cheatsheet
Create archive:
tar -czvf compressed_file.tar.gz original_file.sql
Extract files:
tar -xzvf compressed_file.tar.gz
Keep running ssh command after disconnecting from the server
nohup database_migration.sh &
nohupwill take care of running the command and forward command output tonohup.out&will run the command in the background
Use tail -f nohup.out to get the output from the command
Configure HP printer in fedora
Default Printer application in GNOME (fedora 33) is not able to successfully configure wireless printer, it needs to be done manually:
sudo dnf install hplip hplip-gui
sudo hp-setup
Select Network/Ethernet/Wireless network and your printer will appear in the list. Follow the instructions and add the printer.
List files installed by a package
To list all files installed by dnf package:
rpm -ql dnf
top-like application for intel GPU
Top-like application to monitor performance of intel GPU:
sudo dnf install igt-gpu-tools
sudo intel_gpu_top
Playing 4k video sample on youtube (intel i3-8100T):
intel-gpu-top: Intel Coffeelake (Gen9) @ /dev/dri/card0 - 1063/1083 MHz; 1% RC6; 7.35/19.18 W; 467 irqs/s
IMC reads: 6889 MiB/s
IMC writes: 3901 MiB/s
ENGINE BUSY MI_SEMA MI_WAIT
Render/3D/0 98.29% |██████████████████████████████████▍| 0% 0%
Blitter/0 0.00% | | 0% 0%
Video/0 0.00% | | 0% 0%
VideoEnhance/0 0.00% | | 0% 0%
Playing the same video in 1080p (intel i3-8100T)::
intel-gpu-top: Intel Coffeelake (Gen9) @ /dev/dri/card0 - 591/ 591 MHz; 30% RC6; 3.06/ 6.47 W; 474 irqs/s
IMC reads: 4058 MiB/s
IMC writes: 2654 MiB/s
ENGINE BUSY MI_SEMA MI_WAIT
Render/3D/0 55.64% |███████████████████▍ | 0% 0%
Blitter/0 0.00% | | 0% 0%
Video/0 0.00% | | 0% 0%
VideoEnhance/0 0.00% | | 0% 0%
Install multimedia codecs in fedora
If you are experiencing high CPU usage when watching videos on youtube, verify that the following packages are installed (requires RPMFusion repository):
# RPMFuison repositories
sudo dnf install https://mirrors.rpmfusion.org/free/fedora/rpmfusion-free-release-$(rpm -E %fedora).noarch.rpm https://mirrors.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-$(rpm -E %fedora).noarch.rpm
# Codecs
sudo dnf install gstreamer1-plugins-{bad-\*,good-\*,base} gstreamer1-plugin-openh264 gstreamer1-libav --exclude=gstreamer1-plugins-bad-free-devel
sudo dnf install lame\* --exclude=lame-devel
sudo dnf group upgrade --with-optional Multimedia
CPU usage for i3-8100T is down from 80% to 50% with this video sample
Monitor thread count
watch -n 0.5 "ps -eLf | grep traffic_server | wc -l"
High CPU usage on youtube in fedora
I’ve started to experience quite high CPU usage when watching youtube videos on 1440p screen (video sample). By default, youtube loads videos in VP9 codec. Using this codec results in 80% CPU usage (i3-8100T). By installing this extension enhanced-h264ify and by blocking VP8, VP9 and AV1, youtube will load videos in avc1(h.264) codec. The CPU usage is down to about 30%.
Unfortunately, this will disable all 4k videos - they are available only in VP9.
Add exit code to the command line
Some examples to add exit code to command line prompt in bash (put it into ~/.bashrc):
export PS1="\[\033[01;31m\]\$([ \$? == 0 ] || echo \"!\$? \" )\[\033[00m\]\[\033[01;32m\]\t \[\033[01;34m\]\w\[\033[00m\]\[\033[1;32m\]\n\$ \[\033[m\]"
Add to the default PS1 in CentOS:
export PS1="\[\033[01;31m\]\${?##0}\[\033[00m\][\u@\h \W]\\$"
Disable touchpad in Microsoft All-in-one media keyboard
List all available input devices:
$ xinput list
⎡ Virtual core pointer id=2 [master pointer (3)]
⎜ ↳ Virtual core XTEST pointer id=4 [slave pointer (2)]
⎜ ↳ Logitech M185 id=10 [slave pointer (2)]
⎜ ↳ Microsoft Microsoft® Nano Transceiver v2.0 Consumer Control id=14 [slave pointer (2)]
⎜ ↳ Microsoft Bluetooth Mouse id=20 [slave pointer (2)]
⎜ ↳ Microsoft Microsoft® Nano Transceiver v2.0 Consumer Control id=13 [slave pointer (2)]
⎜ ↳ Microsoft Microsoft® Nano Transceiver v2.0 Mouse id=12 [slave pointer (2)]
⎣ Virtual core keyboard id=3 [master keyboard (2)]
↳ Virtual core XTEST keyboard id=5 [slave keyboard (3)]
↳ Power Button id=6 [slave keyboard (3)]
↳ Video Bus id=7 [slave keyboard (3)]
↳ Power Button id=8 [slave keyboard (3)]
↳ Sleep Button id=9 [slave keyboard (3)]
↳ Microsoft Microsoft® Nano Transceiver v2.0 id=11 [slave keyboard (3)]
↳ Microsoft Microsoft® Nano Transceiver v2.0 System Control id=15 [slave keyboard (3)]
↳ Dell WMI hotkeys id=16 [slave keyboard (3)]
↳ Logitech M185 id=17 [slave keyboard (3)]
↳ Microsoft Microsoft® Nano Transceiver v2.0 Consumer Control id=18 [slave keyboard (3)]
↳ Microsoft Microsoft® Nano Transceiver v2.0 Consumer Control id=19 [slave keyboard (3)]
↳ Microsoft Bluetooth Mouse Keyboard id=21 [slave keyboard (3)]
The touchpad device is known as Microsoft Microsoft® Nano Transceiver v2.0 in the system. Disable it with this command:
xinput disable 12
And enable it again with this command:
xinput enable 12
Or one-liner:
xinput enable `xinput list | grep "Microsoft Microsoft® Nano Transceiver v2.0 Mouse" | grep -oP "id=[0-9]*" | grep -oP "[0-9]*"`