Attention: this is the key used to sign the certificate requests, anyone holding this can sign certificates on your behalf. So keep it in a safe place!
openssl genrsa -des3 -out rootCA.key 4096
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 |
FWIW: I (@rondy) am not the creator of the content shared here, which is an excerpt from Edmond Lau's book. I simply copied and pasted it from another location and saved it as a personal note, before it gained popularity on news.ycombinator.com. Unfortunately, I cannot recall the exact origin of the original source, nor was I able to find the author's name, so I am can't provide the appropriate credits.
# Author: Pieter Noordhuis | |
# Description: Simple demo to showcase Redis PubSub with EventMachine | |
# | |
# Update 7 Oct 2010: | |
# - This example does *not* appear to work with Chrome >=6.0. Apparently, | |
# the WebSocket protocol implementation in the cramp gem does not work | |
# well with Chrome's (newer) WebSocket implementation. | |
# | |
# Requirements: | |
# - rubygems: eventmachine, thin, cramp, sinatra, yajl-ruby |
-- show running queries (pre 9.2) | |
SELECT procpid, age(clock_timestamp(), query_start), usename, current_query | |
FROM pg_stat_activity | |
WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%' | |
ORDER BY query_start desc; | |
-- show running queries (9.2) | |
SELECT pid, age(clock_timestamp(), query_start), usename, query | |
FROM pg_stat_activity | |
WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%' |
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.
A curated list of AWS resources to prepare for the AWS Certifications
A curated list of awesome AWS resources you need to prepare for the all 5 AWS Certifications. This gist will include: open source repos, blogs & blogposts, ebooks, PDF, whitepapers, video courses, free lecture, slides, sample test and many other resources.
sudo apt-get update | |
sudo apt-get install libfreetype6 libfreetype6-dev libfontconfig | |
# /etc/apt/sources.list should contain these: | |
# deb http://us.archive.ubuntu.com/ubuntu/ lucid multiverse | |
# deb-src http://us.archive.ubuntu.com/ubuntu/ lucid multiverse | |
# deb http://us.archive.ubuntu.com/ubuntu/ lucid-updates multiverse | |
# deb-src http://us.archive.ubuntu.com/ubuntu/ lucid-updates multiverse | |
sudo echo ttf-mscorefonts-installer msttcorefonts/accepted-mscorefonts-eula select true | sudo debconf-set-selections |
This gist assumes:
# | |
# Wide-open CORS config for nginx | |
# | |
location / { | |
if ($request_method = 'OPTIONS') { | |
add_header 'Access-Control-Allow-Origin' '*'; | |
# |