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@bmeck
bmeck / Readme.md
Created April 3, 2012 15:02
Simple Vertical Load Balancing for TCP in Node.js

About

This is the most basic example of vertical scaling by transferring connections to workers, rather than sharing server sockets. It was presented at JSConf US 2012. With this you can create some interesting balancing algorithms that cluster would defer to internal/OS logic.

Exercises

A good first project when working with this is to implement sticky sessions based upon connection.remoteAddress and/or connection.remotePort.

A good advanced project is to change from a TCP based balancer to a HTTP(S) one and balance based upon not just connection.remoteAddress etc. but also on the protocol and/or Host header.

Installation

FreeBSD

portmaster irc/irssi
portmaster irc/irssi-xmpp

OS X

brew install irssi

@GABeech
GABeech / haproxy.cfg
Created August 21, 2014 18:35
Stack Exchange HAProxy
# This is an example of the Stack Exchange Tier 1 HAProxy config
# The only things that have been changed from what we are running are:
# 1. User names have been removed
# 2. All Passwords have been remove
# 3. IPs have been changed to use the example/documentation ranges
# 4. Rate limit numbers have been changed to randome numbers, don't read into them
userlist stats-auth
group admin users $admin_user
user $admin_user insecure-password $some_password
@kgorskowski
kgorskowski / coreos-ecs-agent-cloudformation.template
Last active December 31, 2017 14:35
AWS CloudFormation Template for CoreOS stable including AWS ECS Agent. Provide ECS - Cluster and IAM Role, otherwise the ECS service will not work
{
"AWSTemplateFormatVersion": "2010-09-09",
"Description": "CoreOS on EC2: http://coreos.com/docs/running-coreos/cloud-providers/ec2/",
"Mappings" : {
"RegionMap" : {
"eu-central-1" : {
"AMI" : "ami-487d4d55"
},
@lornajane
lornajane / mac.md
Last active June 21, 2024 13:07
Keyboard Only OS X

Keyboard-only Mac Cheatsheet

Hi, I'm Lorna and I don't use a mouse. I have had RSI issues since a bad workstation setup at work in 2006. I've tried a number of extra hardware modifications but what works best for me is to use the keyboard and only the keyboard, so I'm in a good position and never reaching for anything else (except my coffee cup!). I rather unwisely took a job which required me to use a mac (I've been a linux user until now and also had the ability to choose my tools carefully) so here is my cheatsheet of the apps, tricks and keyboard shortcuts I'm using, mostly for my own reference. Since keyboard-only use is also great for productivity, you may also find some of these ideas useful, in which case at least something good has come of this :)

Apps List

There's more detail on a few of these apps but here is a quick overview of the tools I've installed and found helpful

Tool Link Comments
@codefromthecrypt
codefromthecrypt / opentracing-zipkin.md
Last active October 27, 2021 01:44
My ramble on OpenTracing (with a side of Zipkin)

I've had many people ask me questions about OpenTracing, often in relation to OpenZipkin. I've seen assertions about how it is vendor neutral and is the lock-in cure. This post is not a sanctioned, polished or otherwise muted view, rather what I personally think about what it is and is not, and what it helps and does not help with. Scroll to the very end if this is too long. Feel free to add a comment if I made any factual mistakes or you just want to add a comment.

So, what is OpenTracing?

OpenTracing is documentation and library interfaces for distributed tracing instrumentation. To be "OpenTracing" requires bundling its interfaces in your work, so that others can use it to time distributed operations with the same library.

So, who is it for?

OpenTracing interfaces are targeted to authors of instrumentation libraries, and those who want to collaborate with traces created by them. Ex something started a trace somewhere and I add a notable event to that trace. Structure logging was recently added to O

@StevenACoffman
StevenACoffman / _MicroService Proxy Gateway Solutions.md
Last active September 28, 2023 14:54
Microservice Proxy/Gateway Solutions

MicroService Proxy Gateway Solutions

Kong, Traefik, Caddy, Linkerd, Fabio, Vulcand, and Netflix Zuul seem to be the most common in microservice proxy/gateway solutions. Kubernetes Ingress is often a simple Ngnix, which is difficult to separate the popularity from other things.

Github Star Trend:

Github Star History for Kong vs traefik vs fabio vs caddy vs Zuul

This is just a picture of this link from March 2, 2019

Originally, I had included some other solution

# Split all objects and pass them to each filter below
# Create/Delete Namespace
(select(.verb == "create" and .objectRef.resource=="namespaces") |
"[" + .stageTimestamp + "] " + "Namespace Created: name=" + .objectRef.name),
(select(.verb == "delete" and .objectRef.resource=="namespaces") |
"[" + .stageTimestamp + "] " + "Namespace Deleted: name=" + .objectRef.name),
# Create/Delete Deployment
@kislayverma
kislayverma / steve-yegge-google-platform-rant.md
Created December 26, 2019 07:11
A copy (for posterity) of Steve Yegge's internal memo in Google about what platforms are and how Amazon learnt to build them

I was at Amazon for about six and a half years, and now I've been at Google for that long. One thing that struck me immediately about the two companies -- an impression that has been reinforced almost daily -- is that Amazon does everything wrong, and Google does everything right. Sure, it's a sweeping generalization, but a surprisingly accurate one. It's pretty crazy. There are probably a hundred or even two hundred different ways you can compare the two companies, and Google is superior in all but three of them, if I recall correctly. I actually did a spreadsheet at one point but Legal wouldn't let me show it to anyone, even though recruiting loved it.

I mean, just to give you a very brief taste: Amazon's recruiting process is fundamentally flawed by having teams hire for themselves, so their hiring bar is incredibly inconsistent across teams, despite various efforts they've made to level it out. And their operations are a mess; they don't really have SREs and they make engineers pretty much do everything,

@max-rocket-internet
max-rocket-internet / prom-k8s-request-limits.md
Last active June 5, 2024 02:27
How to display Kubernetes request and limit in Grafana / Prometheus properly

CPU: percentage of limit

A lot of people land when trying to find out how to calculate CPU usage metric correctly in prometheus, myself included! So I'll post what I eventually ended up using as I think it's still a little difficult trying to tie together all the snippets of info here and elsewhere.

This is specific to k8s and containers that have CPU limits set.

To show CPU usage as a percentage of the limit given to the container, this is the Prometheus query we used to create nice graphs in Grafana:

sum(rate(container_cpu_usage_seconds_total{name!~".*prometheus.*", image!="", container_name!="POD"}[5m])) by (pod_name, container_name) /