Category Archives: Programming

Compiler bug? Linker bug? Windows Kernel bug.

See the end of the post for an October 2018 bug fix update, or read the whole story: Flaky failures are the worst. In this particular investigation, which spanned twenty months, we suspected hardware failure, compiler bugs, linker bugs, and … Continue reading

Posted in Debugging, Investigative Reporting, Programming | Tagged , , , | 66 Comments

Zombie Processes are Eating your Memory

Zombies probably won’t consume 32 GB of your memory like they did to me, but zombie processes do exist, and I can help you find them and make sure that developers fix them. Tool source link is at the bottom. … Continue reading

Posted in Debugging, Investigative Reporting, Performance, Programming, Rants | Tagged , , | 81 Comments

Delete an inline function, save 794 kB

In the previous episode of “Simple Changes to Shrink Chrome” I discussed how deleting ‘const’ from a few key locations could lead to dramatic size savings, due to a VC++ compiler quirk. In this episode I’ll show how deleting an … Continue reading

Posted in Performance, Programming, Visual Studio | Tagged , , | 13 Comments

Add a const here, delete a const there…

Update, February 2019: Two years later the VC++ bug I reported here still exists, even in VS 2019 preview. However Chromium no longer builds with VC++ so I’m reverting the changes where I deleted const in order to make some … Continue reading

Posted in Performance, Programming, Visual Studio | Tagged , , | 29 Comments

VC++ /arch:AVX option – unsafe at any speed

Microsoft’s VC++ compiler has an option to generate instructions for new instruction sets such as AVX and AVX2, which can lead to more efficient code when running on compatible CPUs. So, an obvious tactic is to compile critical math-heavy functions … Continue reading

Posted in Programming, Visual Studio | Tagged , , , , | 34 Comments

Zeroing Memory is Hard (VC++ 2015 arrays)

Quick, what’s the difference between these two C/C++ definitions of initialized local variables? char buffer[32] = { 0 };char buffer[32] = {}; One difference is that the first is legal in C and C++, whereas the second is only legal … Continue reading

Posted in Performance, Programming, Visual Studio | Tagged , , | 23 Comments

Compiler Bugs Found When Porting Chromium to VC++ 2015

Moving a big software project to a new compiler can be a lot of work, and few projects are bigger than Chromium. In addition to the main Chromium repository, which includes all of Blink, there are over a hundred other … Continue reading

Posted in Programming, Visual Studio | Tagged , , , | 35 Comments

Power Wastage On An Idle Laptop

Ever since I upgraded to Windows 10 it’s felt like my battery life is worse. My suspicion was various scanning tasks that were springing to life more frequently, but it was just a hunch. So, I did what I do … Continue reading

Posted in Investigative Reporting, Performance, Programming, uiforetw, xperf | Tagged , | 33 Comments

Thread Naming in Windows: Time for Something Better

Windows lets you give names to the threads in your process which can then be displayed by debuggers. This is a great idea, but the implementation is showing its age – it’s time for some fixes, or something better. Update, … Continue reading

Posted in Debugging, Programming, Visual Studio | Tagged , , , | 23 Comments

Xperf Basics: Recording a Trace (the ultimate easy way)

This post can be found through https://tinyurl.com/etwtracing, and an alternate version of these instructions can be found here. If your Windows computer is running slowly – if a program takes a long time to launch, if a game has a … Continue reading

Posted in Performance, Programming, uiforetw, xperf | Tagged , , | 50 Comments