john quinn's blog

a while ago i posted some performance benchmarks for drupal running on a variety of servers in amazon's elastic compute cloud.

amazon have just released ebs, the final piece of technology that makes their ec2 platform really viable for running lamp stacks stuck as drupal.

ebs, the "elastic block store", provides sophisticated storage for your database instance, with features including:

• high io throughput
• data replication
• large storage capacity
• hot backups using snapshots
• instance type portability e.g. quickly swapping your database hardware for a bigger machine.

recently i posted some encouraging performance benchmarks for drupal running on a variety of servers in amazon's elastic compute cloud. while the performance was encouraging, the suitability of this environment for running lamp stacks was not. ec2 had some fundamental issues including a lack of static ip addresses and no viable persistent storage mechanism.

amazon are quickly rectifying these problems, and recently announced elasic ip addresses; a "static" ip address that you own and can dynamically point at any of your instances.

today amazon indicated that persistent storage will soon be available.

backups are boring, but we all know how important they are. backups can also be quite powerful when working with xen virtualization, since xen allows for convenient back-up and restore of entire systems.

i've recently been working on a flexible, general-purpose script enabling incremental backups of complete xen guests, optimized for secure, distributed environments; xenBackup. if you're working with xen, you might find it useful.

the xenBackup script leverages open-source components like ssh, rsync, and rdiff-backup to create a simple, efficient and functional solution.

amazon's elastic compute cloud, "ec2", provides a flexible and scalable hosting option for applications. while ec2 is not inherently suited for running application stacks with relational databases such as lamp, it does provide many advantages over traditional hosting solutions.

in this article we get a sense of lamp performance on ec2 by running a series of benchmarks on the drupal cms system. these benchmarks establish read throughput numbers for logged-in and logged-out users, for each of amazon's hardware classes.

we also look at op-code caching, and gauge it's performance benefit in cpu-bound lamp deployments.

in my previous blog, i go over a simple how-to for setting up xen on etch. in this configuration the xen guests are only visible to the xen-host, and any services on the xen-hosts must be accessed via port forwarding, tunneling etc.

for some applications, a bridging configuration works better. you can set this up as follows:

xen is a free software virtual machine monitor for IA-32, x86-64, IA-64 and PowerPC architectures. it runs on a host operating system and allows several guest operating systems to be run on top of the host on the same computer hardware at the same time.

there are many ways to setup xen, but i've put together a simple step-by-step guide to get a working xen system based on debian etch. easy as pie.