@TBugReporter It may also be an issue that is happening this week. The second Tuesday of a month is Microsoft’s “Update Tuesday”. Microsoft’s update process will lock the c: file system, do a bunch of stuff, and then unlock for a moment.
My desktop is getting clobbered and it’s particularly noticeable when dealing with large files in Notepad++. For example, today Notepad++ performance is sluggish but usable for normal size files. I opened a 175 mb (3 million line) file in Notepad++. Ctrl+End to get to the bottom of the file hung Notepad++ for about a minute. Now when I switch to another tab for a normal file it snaps over to the new tab. I switch back to the large file and it hangs for eight or nine seconds before it shows me the tab.
It does seem like Notepad++ and/or Scintilla does an unusual amount of something to figure out what needs to get painted when the view window is at the bottom of a large file. I ran a profiler but there’s next to zero disk I/O from Notepad++ when switching tabs. It checks the files on-disk size and time stamps as part of switching but that operation took 13 microseconds. Without a bunch of time consuming digging, I have no idea why Notepad++ is stalling for eight or nine seconds.
I did verify that it’s the scroll window being at the bottom of the file and not the caret position. I also saw that Notepad++ hangs with seemingly zero system calls and then after eight or nine seconds there is that 13 microsecond burst of activity.
I suspect the machine will get back to its normal speedy self once the Windows updates plus Microsoft Defender stuff is done.