The only books on capacity planning I’ve ever skimmed my way through have been dense, dull tomes of long mathematical formulas, advice that’s hard to use in any practical way and page counts in the treble digits. Thankfully John Allspaw has bucked this trend with The Art of Capacity Planning and instead written a slender, thought provoking, book. The main focus of the book is that measurement is good, blind guessing is bad and that capacity planning, like security, is an ongoing process. Read on →

Near the middle of December I lost a very dear, and constant, companion - my Sony Vaio ‘some model number or other’. After nearly five years the laptop stopped charging and it wasn’t worth paying for the repairs. I put off getting a replacement for as long as I could but while I had the work laptop as a standby I needed a machine I could treat as my own. Something outside the company security policy. Read on →

I recently watched the first in the series of the Pragmatic Programmers Erlang in Practice Screencasts (by Kevin Smith - no, not that Kevin Smith). As I’ve not seen them discussed that much else where I thought I’d jot down my thoughts. First up a disclaimer/warning - I’m not an Erlang person and despite the title of ‘Episode 1’ this series of screencasts is not aimed at people with no experience in the language. Read on →

Behind every good manager lurks dozens of bad ones. While Behind Closed Doors is full of mostly common sense tips it’s uncommon to deal with management that actually apply more than a couple of them. It’s an easy, quick read and an ideal gift for that special manager in your life that you really wished wasn’t. 7⁄10 The Python Phasebook is a concise, well written set of examples. Each ‘phrase’ is a short task with some sample code that shows one of the possible solutions. Read on →

- file_move_safe(move_from_path, move_to_path) + move_file(move_from_path, move_to_path) Is move_file not as safe as file_move_safe? Is it safer? Dare I read the other diffs to find out? Am I better off not knowing?

It’s actually a good month for dynamic language fans in London as we’ve got both the London Perl Workshop and the inaugural Ruby Manor - both of which I’ll be attending. Although, as a sysadmin, I feel a little bad about not making it to the Linux 2008 event (organised by the UKUUG) I couldn’t really justify the time and cost this year. The talks were a decent selection but not enough to get me up to Manchester on my own budget for a weekend. Read on →

I’ve been spending a fair amount of time recently trying to choose my Language of the year for 2009. I’ve always been a dynamic language fan (yes, I know this means I should be looking further afield for the next one) and I was surprised at how different even such a common task as joining all the elements of an array together, using a given separator, looks between them. First let’s look at the big three, including perl, my current favourite. Read on →

You know what the best way to start the day is? I’m pretty sure that it doesn’t include a production web server putting its file systems in to read only mode. When this happens most local commands don’t work - init, shutdown, telnit and reboot all stop being useful and you have to resort to desperate measures… and here’s the desperate measure of the day. First, check that your system supports the magic sysreq key - $ cat /proc/sys/kernel/sysrq 1 # nonzero is good Now you know you have the power to destroy your system through a single incorrect character, have a look at the Redhat Sysrq command reference (you want the ‘sysrq’ section). Read on →

I made it along to my first ever London Python User Group tonight, and from what the regulars said about the turn out so did a lot of other people. Over 50 people in attendance is very respectable. The first talk was a bit of a let down, it felt really long, quite slow moving and could have been much better as a lightning talk. Shame it was the best part of over an hour. Read on →

You’re in charge of a server that provides two types of assets. The first type is public and its visibility is important to your company. The second should be restricted access only and shouldn’t be public. Now suppose there is a mistake made and the private material is exposed publicly - what’s more important, that the public data is available or that the private data isn’t? Who’d make that decision where you work? Read on →