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What is NUMA (Non-Uniformed Memory Access)

Non-Uniform Memory Access (NUMA) is one of the computer memory design methods used in multiprocessor systems, and the time to access the memory varies depending on the relative position between the memory and the processor. In the NUMA architecture, when a processor accesses its local memory, it is faster than when it accesses the remote memory. Remote memory refers to memory that is connected to another processor, and local memory refers to memory that is connected to its own processor. In other words, it is a technology to increase memory access efficiency while using multiple processors on one motherboard. When a specific processor runs out of memory, it monopolizes the bus by itself, so other processors have to play. , and designate 'access only here', and call it a NUMA node.

1. Check Nodes

lspci | grep -i nvidia
  
01:00.0 VGA compatible controller: NVIDIA Corporation TU106 [GeForce RTX 2060 12GB] (rev a1)

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Table of Contents

• set -e, -u, -x, -o pipefail
• set -e
• set -x
• set -u
• set -o pipefail
• Setting IFS
• Original Reference

set -e, -u, -x, -o pipefail

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Git cheatsheet

Find all instances of text in all commits

git grep "text to look for" $(git rev-list --all)

List commit messages since given commit

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Moving efficiently in the CLI

Copied from: Moving efficiently in the CLI

Github: clementC/my_blog/content/figures/moving_cli.png

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Capture a video of a given X Window with gstreamer.

X Window ID

Get the target window ID with the following:

xwininfo

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#!/bin/bash
# =========================================================================
# Source: https://gist.github.com/lucaspar/27f5e108b80524b315be10b2a9049817
# =========================================================================
# This script will compile and install a static FFmpeg build with
#   support for NVENC in Ubuntu. Developed in Ubuntu 23.10,
#   with NVIDIA Drivers v535.129.03 and CUDA v12.2 with a GPU
#   with CUDA capability 8.6 (RTX 3080) (see ccap below).
# It assumes NVIDA drivers are installed and that you have a
#   CUDA-compatible GPU. You can check installed drivers with:

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#!/usr/bin/env bash

# 1. Download and install the QEMU hook helper from here: https://github.com/PassthroughPOST/VFIO-Tools
# 2. Place this file in /etc/libvirt/hooks/qemu.d/NAME OF YOUR VM/prepare/begin/disable-fb.sh
# 3. Make disable-fb.sh executable.

VM_NAME="$1"
echo "libvirt-qemu disable-fb: Disabling efi-framebuffer to prepare to pass GPU to VM $VM_NAME" > /dev/kmsg 2>&1
echo "efi-framebuffer.0" > /sys/bus/platform/devices/efi-framebuffer.0/driver/unbind

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Encoding high-quality HEVC content in a two-pass manner with FFmpeg - based NVENC encoder on supported hardware:

If you've built ffmpeg as instructed here on Linux and the ffmpeg binary is in your path, you can do fast HEVC encodes as shown below, using NVIDIA's NPP's libraries to vastly speed up the process.

Now, to do a simple NVENC encode in 1080p, (that will even work for Maxwell Gen 2 (GM200x) series), start with:

ffmpeg  -i <inputfile> -pass 1 \
-filter:v hwupload_cuda,scale_npp=w=1920:h=1080:format=nv12:interp_algo=lanczos,hwdownload,format=nv12 \

-c:v hevc_nvenc -profile main -preset slow -rc vbr_2pass \

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Because PowerMizer settings in NVIDIA X Server Settings doesn't persist across sessions, 
attempts to overclock can become a nuisance.

The following documents the three CLI settings to modify the Preferred Mode as desired:

# Auto:
nvidia-settings -a [gpu:0]/GPUPowerMizerMode=2

# Adaptive:
nvidia-settings -a [gpu:0]/GPUPowerMizerMode=0

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It "types" the contents of the clipboard.

Why can't you just paste the contents you ask? Sometimes pasting just doesn't work.

• One example is in system password fields on OSX.
• Sometimes you're working in a VM and the clipboard isn't shared.
• Other times you're working via Remote Desktop and again, the clipboard doesn't work in password boxes such as the system login prompts.
• Connected via RDP and clipboard sharing is disabled and so is mounting of local drives. If the system doesn't have internet access there's no easy way to get things like payloads or Powershell scripts onto it... until now.

Windows

The Windows version is written in AutoHotKey and easily compiles to an executable. It's a single line script that maps Ctrl-Shift-V to type the clipboard.