Writings on various topics (mostly technical) from Oliver Hookins and Angela Collins. We currently reside in Sydney after almost a decade in Berlin, have three kids, and have far too little time to really justify having a blog.
Well, despite my best intentions, here I am again writing Ruby. I decided to automate a small part of some data analysis I've had to do a few times, starting with the database queries themselves. Unfortunately the data is spread over several hosts and databases and the first implementation simply queried them serially. The next iteration used the mysql2 gem's asynchronous query functionality but…
I had a fairly frustrating time today trying to explain to someone that
indeed the order of actions matters very much when trying to recover
failed replication on a MySQL server. We had a good dump from the master
taken with --single-transaction --master-data=2 (yes, all InnoDB
tables here), and had imported it successfully. However, at the critical
moment of reading the binary log name and…
I've been hacking on a small Ruby on Rails project to summarise and then prettily display pmacct traffic data. It's not an original idea by any stretch and in fact is directly inspired by a system we had at my last job. For obvious reasons I have to at least reimplement the idea myself, and while the original was written in Python using PostgreSQL, mine will be using Ruby and MySQL.
One small pain point I've already encountered is the lack of IP address functions in MySQL. PostgreSQL at least as far back as 7.4 has supported IP address functions and in the case when you need to be comparing addresses and summarising based on local subnets they are sorely…
One of my favourite interview questions is about sparse files. I'm constantly surprised at how few people know about them, especially in this day when thin-provisioning of storage is so pervasive you can run into it just about anywhere. Most commonly though, candidates will respond back with something to the effect of "a file with holes in it" which is more or less correct. I think out of everyone…
Here are some of the files from my MySQL talk at Linux Conf AU 2008, where I presented material on replicating, high-availability, load-balanced MySQL.
Enjoy!