I’ve been reading the excellent Technically Speaking newsletter for a while now and when they announced they would be running a mentoring program, I jumped at the chance and applied straight away. The idea was that each applicant had to set themselves speaking goals or identify areas they wanted to ...

This series is an attempt to learn more about how a real-life “Garbage Collector” (GC) works internally, i.e. not so much “what it does”, but “how it does it” at a low-level. I will be mostly be concentrating on the .NET GC, because I’m a .NET developer and also because it’s recently been Open Sourc...

In the previous post I looked at the community involvement in the year since Microsoft open-sourced large parts of the .NET framework. As a follow-up I’m going to repeat that analysis, but this time focussing on the repositories that sit under the ASP.NET umbrella project: MVC - Model view controlle...

A little over a year ago Microsoft announced that they were open sourcing large parts of the .NET framework. At the time Scott Hanselman did a nice analysis of the source, using Microsoft Power BI. Inspired by this and now that a year has passed, I wanted to try and answer the question: How much Com...

This is the part 3 of a mini-series looking at what it might take to build the Stack Overflow Tag Engine, if you haven’t read part 1 or part 2, I recommend reading them first. Complex boolean queries One of the most powerful features of the Stack Overflow Tag Engine is that it allows you to do compl...

I’ve added a Resources and Speaking page to my site, check them out if you want to learn more. There’s also a video available of my NDC London 2014 talk “Performance is a Feature!”. Recap of Stack Overflow Tag Engine This is the long-delayed part 2 of a mini-series looking at what it might take to b...

I’ve added a Resources and Speaking page to my site, check them out if you want to learn more. Stack Overflow Tag Engine I first heard about the Stack Overflow Tag engine of doom when I read about their battle with the .NET Garbage Collector. If you haven’t heard of it before I recommend reading the...

tl;dr Benchmarking is hard, it’s very easy to end up “not measuring, what you think you are measuring” Update (2014-09-23): Sigh - I made a pretty big mistake in these benchmarks, fortunately Reddit user zvrba corrected me: Yep, can’t argue with that, see Results and Resources below for the individu...

In Part 1 I looked at some of the more general performance issues that can be learnt from Stack Overflow (the team/product), in Part 2 I’m looking at some of the examples of coding performance lessons. Please don’t take these blog posts as blanket recommendations of techniques that you should go awa...

This post is part of a semi-regular series, you can find the other entries here and here Before diving into any of the technical or coding aspects of performance, it is really important to understand that the main lesson to take-away from Stack Overflow (the team/product) is that they take performan...

Typemock & JustMock are 2 commercially available mocking tools that let you achieve something that should be impossible. Unlike all other mocking frameworks, they let you mock sealed classes, static and non-virtual methods, but how do they do this? Dynamic Proxies Firstly it’s worth covering how reg...

Apologies to Nitsan Wakart, from whom I shamelessly stole the title of this post! tl;dr The .NET port of HdrHistogram can control the field layout within a class, using the same technique that the original Java code does. Recently I’ve spent some time porting HdrHistogram from Java to .NET, it’s bee...

tl;dr Measuring performance accurately is hard. But it is a whole lot easier if someone with experience takes the time to explain your mistakes to you!! This is an update to my previous post, if you haven’t read that, you might want to go back and read it first. After I published that post, Gil Tene...

There is an update to this post, based on feedback I received. In my last post I talked about the techniques that the Roslyn team used to minimise the effect of the Garbage Collector (GC). Firstly I guess its worth discussing what the actual issue is. GC Pauses and Latency In early versions of the ....

In my previous post, I talked about some of the general performance lessons that can be learnt from the Roslyn project. This post builds on that and looks at specific examples from the code base. Generally the performance gains within Roslyn come down to one thing: Ensuring the garbage collector doe...

At Build 2014 Microsoft open source their next-generation C#/VB.NET compiler, called Roslyn. The project is hosted on codeplex and you can even browse the source, using the new Reference Source browser, which is itself powered by Roslyn (that’s some crazy, meta-recursion going on there!). Easter Egg...