Category: Blog

What is a Quantum Dot TV?

The latest buzzword in TVS is Quantum Dot technology.  To understand it we need to understand how LCDs TVs already work. LCD – These work by having a backlight source (typically a bunch of LEDs) which shines through red, green and blue filters for each dot or pixel.  To create white, all the filters are …

Installing HHVM on Amazon Linux (AWS)

HHVM Alternative to PHP, said to increase speed by up to 40%.  Works similar to java in that it pre-compiles PHP automatically to speed up execution time.  Used by facebook. cd /etc/yum.repos.d wget http://www.hop5.in/yum/el6/hop5.repo echo ‘priority=9’ >> hop5.repo echo ‘includepkgs=glog,tbb’ >> hop5.repo wget http://yum.sexydev.com/sexydev-amazon.repo yum install hhvm  

Usernames for Amazon Linux (AWS) and Ubuntu AMI

For Amazon Linux, the username is “ec2-user”, for ubuntu it is simply “ubuntu”. To connect to them you need the key file that was generated when the instance was created, and the public DNS address.  Use a command like: ssh -i myinstance.pem ec2-user@12.34.56.789 Note: Make sure you have opened up ssh (port 22) access to …

Installing Redis on Amazon Linux (AWS)

redis More modern form of memcached. Said to be superior as of v3 due to clustering support. Also available via Amazon Elasticache.  Find the latest version at http://redis.io/download Update the system, fix the timezone, and install the toolchain yum -y update ln -sf /usr/share/zoneinfo/Australia/Brisbane /etc/localtime yum -y install gcc make Download the latest redis (available from …

What’s the difference between Primary and Extended partitions, and Logical Drives?

This only applies to DOS mode partition tables which are being phased out with the more modern GPT partition tables.  However with DOS partition tables a physical harddrive could only have up to 4 Primary Partitions. If more partitions were needed, the first 3 partitions could be set as Primary, with the 4th being an Extended …