Disabling overcommit on V8 servers like Deno will be incredibly inefficient. Your process might only need ~100MB of memory or so but V8's cppgc caged heap requires a 64GB allocation in order to get a 32GB aligned area in which to contain its pointers. This is a security measure to prevent any possibility of out of cage access.

Maybe it should use MAP_NORESERVE ?

I expect it does already, but I don’t think it would help here:

> In mode 2 the MAP_NORESERVE flag is ignored.

https://www.kernel.org/doc/Documentation/vm/overcommit-accou...