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

digitaljhelms

Branching

Quick Legend

Description, Instructions, Notes

Instance	Branch

Informatic

Quick Installation Howto

0. Make sure you have successfuly set up iPXE, iSCSI target (iSCSI Enterprise Target on Debian works fine for me), TFTP server and some time to spend.
1. Get yourself a NTFS-formatted USB stick.
2. Copy contents of installation DVD into mentioned USB stick.
3. Get a copy of wimboot and load it into your TFTP server.
4. Copy boot/bcd, boot/boot.sdi, sources/boot.wim and bootmgr into TFTP root as well.
5. Create the bootstrap script (included bootstrap.ipxe file) and boot your

sergiitk

OS X terminal tips an tricks

Shell tools

System

• sw_vers — Print Mac OS X operating system version information
• system_profiler — Reports system hardware and software configuration.
• system_profiler SPHardwareDataType — Hardware overview.
• hostinfo — Host information.
• nvram -p — Print all of the firmware variables.
• getconf DARWIN_USER_CACHE_DIR — Retrieve standard configuration variables
• /usr/libexec/path_helper — Helper for constructing PATH environment variable

plentz

# to generate your dhparam.pem file, run in the terminal
openssl dhparam -out /etc/nginx/ssl/dhparam.pem 2048

soarez

How to setup your own CA with OpenSSL

For educational reasons I've decided to create my own CA. Here is what I learned.

First things first

Lets get some context first.

hmartiro

ZeroMQ vs Redis

This document is research for the selection of a communication platform for robot-net.

Goal

The purpose of this component is to enable rapid, reliable, and elegant communication between the various nodes of the network, including controllers, sensors, and actuators (robot drivers). It will act as the core of robot-net to create a standardized infrastructure for robot control.

Requirements:

hfreire

# Install QEMU OSX port with ARM support
sudo port install qemu +target_arm
export QEMU=$(which qemu-system-arm)

# Dowload kernel and export location
curl -OL \
https://github.com/dhruvvyas90/qemu-rpi-kernel/blob/master/kernel-qemu-4.1.7-jessie
export RPI_KERNEL=./kernel-qemu-4.1.7-jessie

# Download filesystem and export location

rudelm

Autofs on Mac OS X

With autofs you can easily mount network volumes upon first access to the folder where you want to mount the volume. Autofs is available for many OS and is preinstalled on Mac OS X so I show you how I mounted my iTunes library folder using this method.

Prepare autofs to use a separate configuration file

autofs needs to be configured so that it knows where to gets its configuration. Edit the file /etc/auto_master and add the last line:

#
# Automounter master map
#

+auto_master # Use directory service

rrafal

package main

import (
	"fmt"
	"encoding/json"
	"github.com/jackc/pgx"
	"log"
)

var schema = `