Denis Denisov denji

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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Moving efficiently in the CLI

Copied from: Moving efficiently in the CLI

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

Capture a video of a given X Window with gstreamer.

X Window ID

Get the target window ID with the following:

xwininfo

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 \

	#!/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:

	# https://wiki.archlinux.org/title/NVIDIA/Tips_and_tricks
	# https://forums.developer.nvidia.com/t/does-modprobe-d-nvidia-conf-nvreg-enablestreammemops-need-to-be-set-for-gpudirect-to-work/79511
	# https://github.com/NVIDIA/open-gpu-kernel-modules/blob/main/src/nvidia/interface/nvrm_registry.h
	# Requires nvidia.ko >= 510.40.3 loaded with PeerMappingOverride=1. https://docs.nvidia.com/nvshmem/install-guide/index.html
	# https://wiki.gentoo.org/wiki/NVIDIA/nvidia-drivers/en
	# https://github.com/ventureoo/nvidia-tweaks
	# https://nvdam.widen.net/s/k8vrp9xkft/tech-overview-magnum-io-1790750-r5-web
	# https://developer.download.nvidia.com/devzone/devcenter/cuda/docs/GPUDirect_Technology_Overview.pdf
	# https://docs.nvidia.com/nvshmem/pdf/NVSHMEM-Installation-Guide.pdf

	#!/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