Thiago Gomes thiagomgo

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.

PSQL

Magic words:

psql -U postgres

Some interesting flags (to see all, use -h or --help depending on your psql version):

-E: will describe the underlaying queries of the \ commands (cool for learning!)
-l: psql will list all databases and then exit (useful if the user you connect with doesn't has a default database, like at AWS RDS)

Print a count of the messages in the queue:

exim -bpc
How to resend frozen messages in exim4 queue

exim -bp | grep frozen | awk '{print $3}' | xargs exim -v -M
Print a listing of the messages in the queue (time queued, size, message-id, sender, recipient):

Deep Dive: PostgreSQL on AWS

When loading data

disable backups (backup_retention=0)
disable multi-AZ and autovacuum
pg_dump -Fc (compressed) and pg_restore -j (parallel)
Increase maintenance_work_mem

	# Description:
	# Runs a command on hubot
	# TOTAL VIOLATION of any and all security!
	#
	# Commands:
	# hubot cmd <command> - runs a command on hubot host

	module.exports = (robot) ->
	robot.respond /CMD (.*)$/i, (msg) ->
	# console.log(msg)

	#
	# Auth filter /etc/fail2ban/filter.d/nginx-auth.conf:
	#
	# Blocks IPs that makes too much accesses to the server
	#
	[Definition]

	failregex = ^<HOST> -."(GET\|POST).HTTP.*"

	ignoreregex =

	#!/bin/bash

	# Start/stop an EC2 instance to use as a ssh tunnel
	# requires the aws package locally -- sudo apt-get install awscli
	#
	# usage: ./tunnel.sh start (spin up EC2 and create the tunnel)
	# ./tunnel.sh stop (terminate the EC2 instance to save money)
	# ./tunnel.sh resume (in case your tunnel is interrupted but the EC2 instance is still running)

	# CHANGE THE PARAMETERS BELOW

	/var/log/awslogs.log {
	daily
	missingok
	notifempty
	size 50M
	create 0600 root root
	delaycompress
	compress
	rotate 4
	postrotate

	echo "Removing requiretty"
	sed -i "s/^.*requiretty/#Defaults requiretty/" /etc/sudoers
	echo "Complete!"

	[program:tomcat6]
	command=/opt/tomcat6-instance/bin/supervisor-wrapper.sh