pinkeen

Run a systemd container using cgroupv2 [NOTES]

Post on r/docker

In theory this would allow the nested systemd init to manage its own resources via slices and scopes - kind of like with LXC's nested mode but without the nasty security implication of bind mounting the real cgroupfs into the container.

Running a systemd container is not the only thing that this would enable - together with fuse-overlayfs it might allow one to run containers inside containers more securely.

The problem is that by default the nested group is mounted ro into the container which should not be necessary according to my research. It gets mounted rw as expected when userns-remap is enabled in Docker what is not desirable for me. I am not sure if docker/moby/containerd is at fault here or if it's a limitation of Linux control groups or user namespaces. It would be great if som

svenevs

Unofficial Installation Guide for librealsense on OSX

These instructions are for how to build librealsense on OSX with OpenMP support.

Install the Dependencies

Setup Brew (the OSX Package Manager)

markreid

Git Flow (with rebasing)

See http://nvie.com/posts/a-successful-git-branching-model/

Features

ursuad

Kafka Topics

List existing topics

bin/kafka-topics.sh --zookeeper localhost:2181 --list

Describe a topic

bin/kafka-topics.sh --zookeeper localhost:2181 --describe --topic mytopic

Purge a topic

bin/kafka-topics.sh --zookeeper localhost:2181 --alter --topic mytopic --config retention.ms=1000

... wait a minute ...

dwbuiten

Problems & Solutions for Interaction Between C and Go

At Vimeo, on the transcoding team, we work a lot with Go, and a lot with C, for various tasks such as media ingest. This means we use CGO quite extensively, and consequently, have run into bits that are perhaps not very well documented, if at all. Below is my effort to document some of the problems we've run into, and how we fixed or worked around them.

Many of these are obviously wrong in retrospect, but hindsight is 20/20, and these problems do exist in many codebases currently.

Some are definitely ugly, and I much welcome better solutions! Tweet me at @daemon404 if you have any, or have your own CGO story/tips, please! I'd love to learn of them.

Table of Contents

reiki4040

package main

import (
	"fmt"
	"os"
	"os/signal"
	"syscall"
)

func main() {

staltz

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

---

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

---

rodw

#!/bin/bash 
# A simple script to backup an organization's GitHub repositories.

#-------------------------------------------------------------------------------
# NOTES:
#-------------------------------------------------------------------------------
# * Under the heading "CONFIG" below you'll find a number of configuration
#   parameters that must be personalized for your GitHub account and org.
#   Replace the `<CHANGE-ME>` strings with the value described in the comments
#   (or overwrite those values at run-time by providing environment variables).

hellerbarde

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

jboner

Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD