Arranging invisible icons in quadratic time

Near the end of January I was pointed to a twitter thread where a Windows user with a powerful machine was hitting random hangs in explorer. Lots of unscientific theories were being proposed. I don’t generally do random analysis of strangers’ performance problems but the case sounded interesting so I thought I’d take a look. Update: if you are running Windows 11 then this issue is now fixed for you, according to the status updates on this github issue. If you are running Windows 10 then… sorry, Microsoft has mostly abandoned that operating system. Freya shared an ETW trace of what was happening on her machine and I took a look using Windows Performance Analyzer (WPA). The first thing I noticed was that the UI Delays graph showed that, as promised, explorer.exe’s thread 7,888 was failing to check for messages for 20.531 seconds. It was hung. Now, explorer.exe has many UI threads so it’s not like the entire process was hung, but one of its windows was definitely hung, it was causing h ... Read full article.