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@jboner
jboner / latency.txt
Last active July 29, 2024 02:23
Latency Numbers Every Programmer Should Know
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
@hellerbarde
hellerbarde / latency.markdown
Created May 31, 2012 13:16 — forked from jboner/latency.txt
Latency numbers every programmer should know

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

@probonopd
probonopd / Send infrared commands from the Arduino to the iRobot Roomba
Created March 17, 2013 10:42
Send infrared commands from the Arduino to the iRobot Roomba. Use a transistor to drive the IR LED from pin D3 for maximal range.
#include <IRremote.h>
/*
Send infrared commands from the Arduino to the iRobot Roomba
by probono
2013-03-17 Initial release
@lalyos
lalyos / README.md
Last active February 28, 2023 03:38
proxy docker /var/run/docker.sock to port 2375 with socat

The new Docker daemon uses port: 2376 with TLS enable by default. Sometimes I want to play with curl on the old plain http port 2375. The trick is: use socat in a container to proxy the unix socket to a real port.

docker run -d \
  --volume /var/run/docker.sock:/var/run/docker.sock \
  --name docker-http \
  deb socat -d -d TCP-L:2375,fork UNIX:/var/run/docker.sock
@mitchellh
mitchellh / setup_winrm.txt
Created June 14, 2015 19:31
Packer 0.8 Windows Example on AWS
<powershell>
winrm quickconfig -q
winrm set winrm/config/winrs '@{MaxMemoryPerShellMB="300"}'
winrm set winrm/config '@{MaxTimeoutms="1800000"}'
winrm set winrm/config/service '@{AllowUnencrypted="true"}'
winrm set winrm/config/service/auth '@{Basic="true"}'
netsh advfirewall firewall add rule name="WinRM 5985" protocol=TCP dir=in localport=5985 action=allow
netsh advfirewall firewall add rule name="WinRM 5986" protocol=TCP dir=in localport=5986 action=allow
@monteslu
monteslu / StandardFirmataWifi_ESP_MDNS.ino
Last active June 17, 2017 00:09
Standard Firmata Wifi also using MDNS for finding the IP of your ESP8266 nodebot
/*
Firmata is a generic protocol for communicating with microcontrollers
from software on a host computer. It is intended to work with
any host computer software package.
To download a host software package, please clink on the following link
to open the list of Firmata client libraries your default browser.
https://github.com/firmata/arduino#firmata-client-libraries
@so0k
so0k / kubectl.md
Last active April 25, 2024 12:40
Playing with kubectl output

Kubectl output options

Let's look at some basic kubectl output options.

Our intention is to list nodes (with their AWS InstanceId) and Pods (sorted by node).

We can start with:

kubectl get no
@BretFisher
BretFisher / docker-for-mac.md
Last active July 9, 2024 11:29
Getting a Shell in the Docker Desktop Mac VM

2021 Update: Easiest option is Justin's repo and image

Just run this from your Mac terminal and it'll drop you in a container with full permissions on the Docker VM. This also works for Docker for Windows for getting in Moby Linux VM (doesn't work for Windows Containers).

docker run -it --rm --privileged --pid=host justincormack/nsenter1

more info: https://github.com/justincormack/nsenter1


@avorobyov
avorobyov / presentation.md
Last active August 23, 2017 02:03
Java in Docker pitfalls presentation

Java in Docker pitfalls


Why Java is a special case

  • JVM ergonomics
  • Libraries ergonomics

JVM and libraries decide how much memory and how many threads to use.

@eddiewebb
eddiewebb / readme.md
Last active June 24, 2024 02:21
Hugo JS Searching with Fuse.js