Much hot air over blinking cursors

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Like any large development project, Fedora has a number of important problems to resolve at any given time. One of those problems is power management and, in particular, power conservation; developers in the Fedora project have also often stated their desire to have a more "green" operating system. So one might think that, when Matthew Garrett came along with a proposal like this

The blinking cursor causes the processor and GPU to be woken up frequently. On one of my test systems, this causes somewhere in the region of 2 Watts of extra power consumption. I'd like to change the default for this to false. Anyone have any objections?

...that the request for objections would yield few responses. What ensued instead was a lengthy discussion (to put it charitably) which made it clear that some users value their by-default blinking cursor far above any other considerations.

Blinking cursors have been targeted by developers concerned about power consumption for some time now. Every transition requires that the system wake up to make the cursor change, and wakeups increase power usage. Beyond that, though, Matthew has written a graphics driver patch that allows the system to put the graphics processor into a sleeping state as well - as long as the screen does not change. Once again, every cursor transition requires powering up the GPU; that is where much of the excess power usage comes from.

This power savings comes at "idle" times, so some detractors pointed out that, on most systems, the screen saver will quickly power down everything when the system is idle. But "idle" in this context means something different: it describes times when nothing is being drawn to the screen. Such periods of idleness come about, for example, during each of your editor's frequent pauses as he ponders what to write next, what to make for lunch, or whether it wouldn't be better to just drop everything and go for a bike ride. It is a different time scale than the screen saver operates on. Idle displays will not come about if frequently-updating applications are running, but, otherwise, it's a common occurrence even on systems which are nominally busy.

Accurate counts of Fedora installations are hard to come by, but most estimates seem to be in the millions. A two-watt power savings over millions of systems implies a total power savings in the megawatt range. Even if the power savings estimates are way off (and there are those who assert that this is the case), it seems like something worth reaching for. After all, it's a simple default change, and anybody who is truly attached to a blinking cursor can change it back - even if Fedora has helpfully hidden the toggle under Preferences/Hardware/Keyboard in the main menu.

Besides, your editor came to a thoroughly objective conclusion many years ago that blinking cursors are an annoying distraction and that any developer implementing such behavior should be sentenced to ten years of COBOL coding under a strobe light.

The arguments against this change seem to fall into two categories. One of those is that users are unable to find their cursor if it does not blink. For example:

The "wins" are massively overhyped, and the loss is users wondering where the damn cursor is (there are good reasons it was made to blink in the first place)

The other argument seems to be along the lines of "but we've always had a blinking cursor." Example:

Blindingly ignoring tradition is patently absurd. We might as well change the slogan to: Fedora: stupid and proud of it!

Numerous other developers have come out in favor of the change. This seems like one of those issues where a full consensus will never develop; so, if this change is to be made, somebody has to just do it despite the flames. It would appear that Matthew has done exactly that. One can only wonder how many more carbon emissions would have been avoided if he hadn't asked for objections first.

