For a game engine where task based structure is important Go would be a pretty poor choice.
I have a game server written in Go.
You don't want a GC in your inner engine loop.
Why not? I expect my typical GC pause times to be 1 or 2 ms under Go 1.7. But if my server had pause times of 20ms, I wouldn't care, so long as it didn't happen more often than once a second or so.
It's very common to issue cache prefetches for the next task as one is spinning down for instance.
Yeah, I've had Go guys say I should give every agent its own goroutine. As it turns out, this can cost 150-300 microseconds every time one of them wakes up. I have a traditional game loop right now.
> I have a game server written in Go.
Game engine != game server.
> Why not? I expect my typical GC pause times to be 1 or 2 ms under Go 1.7. But if my server had pause times of 20ms, I wouldn't care, so long as it didn't happen more often than once a second or so.
We're talking about client-side latency here. You've got 16.6ms to do everything in a game engine. Even 2ms is 1/8th of your frame and a significant amount of work. 20ms is two missed frames which is really bad.
The types of engines where work stealing and task based architecture are prevalent are usually of the AAA variety, where performance is critical and the scenes are either very complex or very large. In this space GC based languages have been limited in scope to gameplay scripting and even then are usually very fast(Lua or equivalent).
> Even 2ms is 1/8th of your frame and a significant amount of work.
And this is targeting a mere 60hz. Oculus DK2s overclocked their LCD panels to run higher than spec (75hz) and shipped even higher refresh rates in CV1 (90hz) because of it's importance in reducing nausea. To say nothing of the enthusiasts running 120hz or 144hz displays - in which case you've blown through more than 1/4th of your frame budget 'at random' (read: you must assume it could happen in any frame) unless you can control when GC occurs.
> 20ms is two missed frames which is really bad.
If you're doing VR, this is bad enough that some of your customers may hurl. I've gone after fixing single frame hitches which were caused by as little as an extra 1ms spike at exactly the wrong time in non VR games. Unfixable 20ms spikes would be a total non-starter.
There's a lot of applications where you can tolerate an extra 1-2ms extra spike. A game server, where network latency is an order of magnitude or two larger, will probably almost always count. And if your improved productivity from using the language lets you optimize away an additional 1-2ms cost elsewhere that you wouldn't have time for otherwise, it can even be worth it.
For me, there's so much stuff that I use to boost my productivity, that's missing from Go - by design no less - that my productivity is going to be going the wrong way.
I have a game server written in Go.
You don't want a GC in your inner engine loop.
Why not? I expect my typical GC pause times to be 1 or 2 ms under Go 1.7. But if my server had pause times of 20ms, I wouldn't care, so long as it didn't happen more often than once a second or so.
It's very common to issue cache prefetches for the next task as one is spinning down for instance.
Yeah, I've had Go guys say I should give every agent its own goroutine. As it turns out, this can cost 150-300 microseconds every time one of them wakes up. I have a traditional game loop right now.