Brainiarc7

Deploying rEFInd on Ubuntu 16.04 LTS with secure boot enabled

Hello guys,

For these dual-booting Ubuntu 16.04 with an alternate operating system in UEFI boot mode, it may often be necessary to use a third-party boot manager such as rEFInd, as it's significantly superior to grub2's on UEFI-capable systems.

This write-up assumes that:

(a). The user is running a current Ubuntu 16.04LTS operating system installation (preferably on a dual-boot system)

Brainiarc7

Transient compute clustering with GNU Parallel and sshfs:

GNU Parallel is a multipurpose program for running shell commands in parallel, which can often be used to replace shell script loops,find -exec, and find | xargs. It provides the --sshlogin and --sshloginfile options to farm out jobs to multiple hosts, as well as options for sending and retrieving static resources and and per-job input and output files.

For any particular task, however, keeping track of which files need to pushed to and retrieved from the remote hosts is somewhat of a hassle. Furthermore, cancelled or failed runs can leave garbage on the remote hosts, and if input and output files are large, sending them to local disk on the remote hosts is somewhat inefficient.

In a traditional cluster, this problem would be solved by giving all nodes access to a shared filesystem, usually with NFS or something more exotic. However, NFS doesn't wo

Brainiarc7

Streaming your Linux desktop to Youtube and Twitch via Nvidia's NVENC and VAAPI:

Considerations to take when live streaming:

The following best practice observations apply when using a hardware-based encoder for live streaming to any platform:

1. Set the buffer size (-bufsize:v) equal to the target bitrate (-b:v). You want to ensure that you're encoding in CBR mode.

2. Set up the encoders as shown:

Brainiarc7

Useful Examples of ffmpeg and GNU parallel on the command-line:

Transcoding FLAC music to Opus:

ffmpeg is a highly useful application for converting music and videos. However, audio transcoding is limited to a a single core. If you have a large FLAC archive and you wanted to compress it into the efficient Opus codec, it would take forever with the fastest processor to complete, unless you were to take advantage of all cores in your CPU.

parallel 'ffmpeg -v 0 -i "{}" -c:a libopus -b:a 128k "{.}.opus"' ::: $(find -type f -name '*.flac')

Transcoding Videos to VP9:

Brainiarc7

To limit a CPU to a certain C-state, you can pass the processor.max_cstate=X option in the kernel line of /boot/grub/grub.conf.

Here we limit the system to only C-State 1:

    kernel /vmlinuz-2.6.18-371.1.2.el5 ... processor.max_cstate=1

On some systems, the kernel can override the BIOS setting, and the parameter intel_idle.max_cstate=0 may be required to ensure sleep states are not entered:

Brainiarc7

Tuning Intel Skylake and beyond for optimal performance and feature level support on Linux:

Note that on Skylake, Kabylake (and the now cancelled "Broxton") SKUs, functionality such as power saving, GPU scheduling and HDMI audio have been moved onto binary-only firmware, and as such, the GuC and the HuC blobs must be loaded at run-time to access this functionality.

Enabling GuC and HuC on Skylake and above requires a few extra parameters be passed to the kernel before boot.

Instructions provided for both Fedora and Ubuntu (including Debian):

Note that the firmware for these GPUs is often packaged by your distributor, and as such, you can confirm the firmware blob's availability by running:

Brainiarc7

Using VAAPI's hardware accelerated video encoding on Linux with Intel's hardware on FFmpeg and libav

Hello, brethren :-)

As it turns out, the current version of FFmpeg (version 3.1 released earlier today) and libav (master branch) supports full H.264 and HEVC encode in VAAPI on supported hardware that works reliably well to be termed "production-ready".

Brainiarc7

Setting up analog surround sound on Ubuntu Linux with a 3 3.5mm capable sound card:

A while back, I received the Logitech Z506 Speaker system, and with Windows, setting it up was a pretty plug and play experience. On Linux, however, its' a wholly different ballgame. For one, there's no Realtek HD Audio control panel here, so what gives? How do you around this problem?

Introducing the tools of the trade:

You'll want to use a tool such as hdajackretask , pavucontrol and pavumeter for the pin re-assignments and audio output monitoring afterwards respectively. The tools are installed by running:

sudo apt-get install alsa-tools-gui pavumeter pavucontrol

Brainiarc7

First, install arch-install-scripts:

sudo pacman -S --needed arch-install-scripts

Secondly, mount your partitions in all the internal hard drives.

Thirdly, generate and validate your config by piping it out to stdout:

Brainiarc7

# first get the PPA repository driver
sudo add-apt-repository ppa:graphics-drivers/ppa

# install nvidai driver 
sudo apt install nvidia-384 nvidia-384-dev

# install other import packages
sudo apt-get install g++ freeglut3-dev build-essential libx11-dev libxmu-dev libxi-dev libglu1-mesa libglu1-mesa-dev

# CUDA 9 requires gcc 6