MC-77633CPU doubles when paused on non-active OS X desktop
When paused on a non-active (background) desktop in OS X or as a fullscreen application in the background (not the Minecraft settings fullscreen; the OS fullscreen), the app's CPU skyrockets to more than double its normal pause level and my computer starts to rapidly heat up.
To replicate:
Launch Minecraft and open up any world.
Hit OS X's green fullscreen icon.
Pause the game and switch back to your normal desktop, leaving the game fullscreen.
The CPU will rapidly increase and after several seconds your computer's fan should start to ramp up. The energy usage will also soar.
Once you switch back to the fullscreen Minecraft, the CPU will drop back down.
Environment
OS X Yosemite 10.10.2
Attachments1
Created Issue:
CPU doubles when paused on non-active OS X desktop
When paused on a non-active (background) desktop in OS X or as a fullscreen application in the background (not the Minecraft settings fullscreen; the OS fullscreen), the app's CPU skyrockets to more than double its normal pause level and my computer starts to rapidly heat up.
To replicate:
Launch Minecraft and open up any world.
Hit OS X's green fullscreen icon.
Pause the game and switch back to your normal desktop, leaving the game fullscreen.
The CPU will rapidly increase and after several seconds your computer's fan should start to ramp up. The energy usage will also soar.Once you switch back to the fullscreen Minecraft, the CPU will drop back down.
Environment
OS X Yosemite 10.10.2
Are you paused via esc menu or paused with another method, that could still be running commands ingame while you are away?
Now noone has answered Are you switching to a SECOND desktop keeping Minecraft at fullscreen on another desktop while you run other process on your second one? Or are you using ONE desktop and minimizing the game to access the apps?
Similar to MC-77633, when Minecraft is running and I switch to another desktop, its CPU usage leaps up. For example, with Minecraft running in the foreground it uses ~60% CPU. When I switch to another desktop, it jumps to 100% CPU, the CPU core temperature rises and the fans come on full blast.
I have Minecraft on what I believe are the default settings: max frame rate 120fps and vsync: on. If I reduce the max frame rate to 60fps, I don't see an increase in CPU usage when I switch to another desktop. I suspect that when Minecraft is on a non-foreground desktop, vsync no longer has any effect, so Minecraft suddenly starts using 100% CPU to try to render as fast as possible.
Ideally, Minecraft would not render at all while on a non-foreground desktop (perhaps not possible, since OSX can still show a realtime preview of other desktops), failing that it would render at a low framerate, and failing that when vsync is enabled it would not render above the vsync rate when on a non-foreground desktop.
Cannot confirm
Could this be a problem with OS X, and the way it handles its fullscreen? What happens when you use Minecrafts built in fullscreen?
When in Minecraft's built in fullscreen, I can't switch desktops, so it isn't an issue. I just tested in on 1.8.7 and it still does it. It's worth noting that Minecraft doesn't have to be full screen. If I leave it as a window and switch desktops, the cpu still shoots up, though it doesn't reach nearly as high as it would with Minecraft fullscreen.
It's possible that it could be an OS X issue, though I have never seen it do it with any other app.
So you are switching to a second desktop? Or do you only have 1 desktop? Do you use any other app that uses Java as minecraft does?
If you are using 2 desktops does the issue persist when only using the one Minecraft is on and not loading up the second desktop?
I don't know macs too well It has been a while since I had one, I don't think I can be much more use without more detailed info.
Hey folks,
I've confirmed this happens on the latest OSX (Mavericks) running MC 1.8.x and Java8.
However, I've noticed that it only happens when you've loaded a world, if you're simply at the title screen the CPU does not spike. This is somehow tied directly to world processing, and only while not using the in-game fullscreen setting (using the OS-level fullscreen/"maximize").
If any additional information is required, please let me know and I will do what I can to gather it.
This really sounds like an issue with OS X and not Minecraft, Sure it is Minecraft interacting with OS X, but If the default fullscreen works and the OS X one doesn't, Then it sounds as if you are using a third party program to go fullscreen. (OS X being the third party)
@John Dame I think we should probably preface the "default fullscreen" working part of this with a "may work, but unable to confirm". While in the in-game fullscreen, you can't switch to an alternate desktop, so it is entirely possible that the same thing could happen if you had the ability to switch when using the in-game fullscreen method.
Now.. the reason I still believe this to be Minecraft specific is due to the fact that ... the CPU spike doesn't happen at the title screen (I've tested this repeatedly) but it does happen when you've loaded a world. If this was an OS-level problem (or third party to Minecraft) it wouldn't matter whether you were on the title screen, in a world, creating a world, on a server, playing locally. For all intents and purposes, the OS should treat it all the same (now, I know technically... it isn't quite that simple but...)
There is something specific to MC when inside a world that is causing the spike when it loses focus and isn't viewable. (a perfect reason for this is... say a user wants to build a very difficult redstone build, needs to go back and forth between a tutorial and their own world. Their CPU would almost constantly sit at peak capacity making the experience unmanageable.)
I think it might be the way OS X handles background spaces, mixed with minecrafts/javas handling of Memory/Processes.
But after searching around online for similar issues with other games I come up with nothing. I cannot help you, Best of luck.
I was just commenting to say that I could confirm the same problem as the OP. Although... it would be great to see this get resolved/fixed at some point.
On a side note; I'm considering putting together an app that spawns a full-screen child process (similar to the MC Launcher + MC Game) and cycles through a bunch of calculations (to try some half-baked attempt at simulating a similar situation that we're seeing with Minecraft), then swapping into the alternate desktop and see if it does the same thing. I can't imagine that it will come up with anything too successful, but if I can replicate it like that, it would possibly point towards OSX and not MC.
Thanks for the replies John.