userguy

#!/bin/bash

echo -e "\nbenchmark.sh -n<number of requests> -c<number of concurrency> <URL1> <URL2> ..."

echo -e "\nEx: benchmark.sh -n100 -c10 http://www.google.com/ http://www.bing.com/ \n"

## Gnuplot settings
echo "set terminal png
set output 'benchmark_${1}_${2}.png'
set title 'Benchmark: ${1} ${2}'

userguy

Elasticsearch: updating the mappings and settings of an existing index

Note: This was written using elasticsearch 0.9.

Elasticsearch will automatically create an index (with basic settings and mappings) for you if you post a first document:

$ curl -X POST 'http://localhost:9200/thegame/weapons/1' -d \
'{
  "_id": 1,

userguy

############### Backup keepalived configuration
#
# Zentrale VRRP-Konfigurationsdatei fuer Backup-Firewall des IWM
#
# ChangeLog:
#
#  23.11.2012  - Torsten Kurbad <t.kurbad@iwm-kmrc.de>
#                * Initiale Version
#
###

userguy

############### Master keepalived configuration
#
# Zentrale VRRP-Konfigurationsdatei fuer primaere Firewall des IWM
#
# ChangeLog:
#
#  23.11.2012  - Torsten Kurbad <t.kurbad@iwm-kmrc.de>
#                * Initiale Version
#
###

userguy

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

userguy

---
# This has been tested with ansible 1.3 with these commands:
#   ansible-playbook -i hosts ansible_conditionals_examples.yaml --extra-vars="hosts=myhosts isFirstRun=false"
#   ansible-playbook -i hosts ansible_conditionals_examples.yaml --extra-vars="hosts=myhosts isFirstRun=true"
#   ansible-playbook -i hosts ansible_conditionals_examples.yaml --extra-vars="hosts=myhosts"
# NB: The type of the variable is crucial!

- name: Ansible Conditionals Examples
  hosts: $hosts
  vars_files:

userguy

Moved to git repository: https://github.com/denji/nginx-tuning

NGINX Tuning For Best Performance

For this configuration you can use web server you like, i decided, because i work mostly with it to use nginx.

Generally, properly configured nginx can handle up to 400K to 500K requests per second (clustered), most what i saw is 50K to 80K (non-clustered) requests per second and 30% CPU load, course, this was 2 x Intel Xeon with HyperThreading enabled, but it can work without problem on slower machines.

You must understand that this config is used in testing environment and not in production so you will need to find a way to implement most of those features best possible for your servers.