Category: Web work

These days, most of my work is very related to the online world. Building web sites, reviewing web applications, integrating with web services, coordinating people who are far away from each other, etc. Whenever I find a new tool or service or an innovative, interesting idea about working online, I share it in this category.

pvm – PHP Process virtual machine for building and executing workflows

At some point last year I wrote the blog post titled “Getting started with workflows in PHP“.  I received quite a bit of feedback about it, but, unfortunately, the priorities at work shifted and I haven’t done much more with workflows since than.

The world, however, hasn’t stopped.  The tools and libraries that existed a year ago are still around and they got a lot better.  Additionally, there are a few new tools that help with workflows, state machines, and the like.

Today I came across a really useful and easy to use tool for building and executing workflows in PHP – pvm, aka PHP Process Virtual Machine.  It’s built and released as Open Source software under MIT license by the excellent guys at Forma-Pro.   If you are still looking for a tool to build and execute workflows, I strongly suggest you give PVM a try.  Given how complex the nature of the problem, this tool is probably the easiest to get started with.

ipstack – IP geolocation and database service

ipstack looks like an excellent IP geolocation service with a beautiful API.  If you haven’t used anything except for the MaxMind GeoIP, give it a try.  Their pricing is quite good, with 10,000 lookups per month going for free.

Gitea – self-hosted Git service

Gitea is yet another alternative to BitBucket, GitHub, and GitLab Cloud.  It’s an open source solution for self-hosting Git repositories.  It’s a fork of Gogs, written in Go, and is available under the MIT license.

Creating a 1.3 Million vCPU Grid on AWS using EC2 Spot Instances and TIBCO GridServer

This Amazon AWS blog post provides a great insight into the benefits of the cloud computing in general and Amazon AWS in particular.  The whole thing is well worth the read, but here are a few of my favorite bits.

The scale:

The grid grew to 61,299 Spot Instances (1.3 million vCPUs drawn from 34 instance types spanning 3 generations of EC2 hardware) as planned, with just 1,937 instances reclaimed and automatically replaced during the run, and cost $30,000 per hour to run, at an average hourly cost of $0.078 per vCPU. If the same instances had been used in On-Demand form, the hourly cost to run the grid would have been approximately $93,000.

The size of the Amazon AWS customers:

1.3 million vCPUs (5x the size of the largest on-premises grid)

The evolution of computing power over the last few years:

To give you a sense of the compute power, we computed that this grid would have taken the #1 position on the TOP 500 supercomputer list in November 2007 by a considerable margin, and the #2 position in June 2008. Today, it would occupy position #360 on the list.

Now, just for fun, exercise the idea of building something like this in house…