Category Archives: Investigative Reporting

A Not-Called Function Can Cause a 5X Slowdown

Posted on December 3, 2018 by brucedawson

Subtitle: Making Windows Slower Part 3: Process Destruction In the summer of 2017 I wrestled with a Windows performance problem. Process destruction was slow, serialized, and was blocking the system input queue, leading to repeated short mouse-movement hangs when building … Continue reading →

Posted in Investigative Reporting, Performance, Programming | Tagged , , | Leave a comment

Making Windows Slower Part 2: Process Creation

Posted on October 15, 2018 by brucedawson

Windows has long had a reputation for slow file operations and slow process creation. Have you ever wanted to make these operations even slower? This weeks’ blog post covers a technique you can use to make process creation on Windows … Continue reading →

Posted in Code Reliability, Investigative Reporting, Performance, Programming, Quadratic | Tagged , , | 7 Comments

24-core CPU and I can’t type an email (part two)

Posted on August 22, 2018 by brucedawson

In my last post I promised to give more details about some rabbit holes that I went down during the investigation, including page tables, locks, WMI, and a vmmap bug. Those details are here, along with updated code samples. But … Continue reading →

Posted in Investigative Reporting, memory, Performance | Tagged , , , | 16 Comments

24-core CPU and I can’t type an email (part one)

Posted on August 16, 2018 by brucedawson

I wasn’t looking for trouble. I wasn’t trying to compile a huge project in the background (24-core CPU and I can’t move my mouse), I was just engaging in that most mundane of 21st century tasks, writing an email at … Continue reading →

Posted in Investigative Reporting, memory, Performance | Tagged , , , | 28 Comments

Making Windows Slower Part 1: File Access

Posted on April 17, 2018 by brucedawson

Windows has long had a reputation for slow file operations and slow process creation. Have you ever wanted to make these operations even slower? This weeks’ blog post covers a technique you can use to make all file operations on … Continue reading →

Posted in Investigative Reporting, Performance, Programming, xperf | Tagged , , | 18 Comments

Compiler bug? Linker bug? Windows Kernel bug.

Posted on February 25, 2018 by brucedawson

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 , , , | 57 Comments

Zombie Processes are Eating your Memory

Posted on February 11, 2018 by brucedawson

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 , , | 74 Comments

Hey Synaptics, Can You Please Stop Polling!

Posted on September 5, 2017 by brucedawson

TL;DR – be wary of buying a Lenovo laptop or any other laptop that uses a Synaptics touch pad until Synaptics ships a fixed driver. Their driver has a memory leak and they have a battery-life bug that causes Windows … Continue reading →

Posted in Investigative Reporting, Uncategorized | 30 Comments

What is Windows *doing* while hogging that lock

Posted on July 27, 2017 by brucedawson

Earlier this month I wrote about how Windows 10 holds a lock during too much of process destruction, which both serializes this task and causes mouse-cursor hitches and UI hangs (because the same lock is used for these UI tasks). … Continue reading →

Posted in Investigative Reporting, uiforetw, xperf | Tagged , , | 12 Comments

24-core CPU and I can’t move my mouse

Posted on July 9, 2017 by brucedawson

This story begins, as they so often do, when I noticed that my machine was behaving poorly. My Windows 10 work machine has 24 cores (48 hyper-threads) and they were 50% idle. It has 64 GB of RAM and that … Continue reading →

Posted in Investigative Reporting, uiforetw, xperf | Tagged , , | 209 Comments