alt Hacker NewsGo won’t put large allocations on the stack even if escape analysis would permit it, so generally speaking this should only be a concern if you have very deep recursion (in which case you might have to worry about stack overflows anyway).
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Yokohiii • last Thursday at 4:50 PM
Escape analysis accounts for size, so it wouldn't even permit it.
The initial stack size seems to be 2kb, a more on a few systems. So far I understand you can allocate a large local i.e. 8kb, that doesn't escape and grow the stack immediately. (Of course that adds up if you have a chain of calls with smaller allocs). So recursion is certainly not the only concern.
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> Go won’t put large allocations on the stack even if escape analysis would permit it
Depends what you mean by “large”. As of 1.24 Go will put slices several KB into the stack frame:
Goes on the stack if it does not escape (you can see Go request a large stack frame) goes on the heap (Go calls runtime.makeslice).Interestingly arrays have a different limit: they respect MaxStackVarSize, which was lowered from 10MB to 128 KB in 1.24.
If you use indexed slice literals gc does not even check and you can create megabyte-sized slices on the stack.