Category Archives: uiforetw

Heap Snapshots–Tracing All Heap Allocations

Posted on October 27, 2019 by brucedawson

I’ve recently started using heap snapshots on Windows to track heap allocations. I was able to use heap snapshots to record call stacks for all outstanding allocations in Chrome’s browser process over a full two weeks, letting me account for … Continue reading →

Posted in Documentation, Performance, Programming, uiforetw, xperf | Tagged , | 23 Comments

63 Cores Blocked by Seven Instructions

Posted on October 20, 2019 by brucedawson

I seem to have a habit of writing about super powerful machines whose many cores are laid low by misuse of locks. So. Yeah. It’s that again. But this one seems particularly impressive. I mean, how often do you have … Continue reading →

Posted in Investigative Reporting, Performance, Programming, Quadratic, uiforetw, xperf | Tagged , , | 12 Comments

Taskbar Latency and Kernel Calls

Posted on September 8, 2019 by brucedawson

I work quickly on my computer and I get frustrated when I am forced to wait on an operation that should be fast. A persistent nuisance on my over-powered home laptop is that closing windows on the taskbar is slow. … Continue reading →

Posted in Investigative Reporting, Performance, uiforetw, xperf | Tagged , , , | 34 Comments

When Your Profiler Lies

Posted on December 9, 2018 by brucedawson

Last week I wrote about the performance consequences of inadvertently loading gdi32.dll into processes that are created and destroyed at very high rates. This week I want to share some techniques for digging deeper into this behavior, and the odd … Continue reading →

Posted in Investigative Reporting, Performance, Programming, uiforetw, xperf | Tagged , , | 12 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

WPA Symbol Loading is Much Faster, but Broken for Chrome

Posted on November 7, 2016 by brucedawson

There’s good news, and there’s bad news. The good news is that the latest Windows Performance Analyzer (WPA), the visualization tool for ETW (Event Tracing for Windows) traces, can now load symbols faster than ever before – it’s multi-threaded, and … Continue reading →

Posted in uiforetw | Tagged , , , | 3 Comments

ETW Flame Graphs Made Easy

Posted on September 5, 2016 by brucedawson

A bit over three years ago I wrote about how to use flame graphs to visualize CPU Usage (Sampled) data from ETW, and a year ago I added flame graph support to UIforETW. However these techniques are clumsy and slow … Continue reading →

Posted in Performance, uiforetw, xperf | Tagged , , | 28 Comments

UIforETW is No Longer a CPU Hog

Posted on May 12, 2016 by brucedawson

A few months ago I wrote about how many processes on my system were waking up and wasting CPU time for no good reason, thus wasting battery power, electricity, and CPU power. I was surprised that nobody called me out … Continue reading →

Posted in Performance, uiforetw, xperf | Tagged , | 6 Comments

Power Wastage On An Idle Laptop

Posted on March 8, 2016 by brucedawson

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 , | 37 Comments