In an interesting post aimed at the more casual reader, the CTO of Croteam has now written up a post about 'The Elusive Frame Timing'.
An issue that has been around for years, is that while a game may run at 60FPS you might experience stuttering, even though the FPS is good. It's not a problem with one particular developer either, many games do suffer from the same issue. It's written to go along with the talk they did at GDC this year (slides here). What's interesting, is how long they've been researching this and trying to solve it.
They showed two videos to highlight the problem, the first is this one which should run perfectly smoothly and this one showing what they're calling "Heartbeat" stutter. Having two monitors next to each other, playing both at the same time made it really easy to see. To make it easier to spot, they did another video with them sliced together, the smooth version being on top and you can easily notice the difference, especially as it looks like it's tearing in the middle.
It seems Vulkan is a bit ahead of the game here, with the VK_GOOGLE_display_timing extension, which Croteam have been experimenting with. Although, support for it is quite limited currently.
A really interesting read, if still a bit over my head overall. You can read the full post on Medium.