alt Hacker NewsInteresting.
I gotta admit that my smell test tells me that this is a step backwards; at least naively (I haven't looked through the code thoroughly yet), this just kind of feels like we're going back to pre-protected-memory operating systems like AmigaOS; there are reasons that we have the process boundary and the overhead associated with it.
If there are zero copies being shared across threadprocs, what's to stop Threadproc B from screwing up Threadproc A's memory? And if the answer to this is "nothing", then what does this buy over a vanilla pthread?
I'm not trying to come off as negative, I'm actually curious about the answer to this.
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I think it is possible for B to screw up A when you share a pointer but otherwise unlikely. B doing stuff with B's memory is unlikely to screw up A.
Judging by the description, it's exactly like AmigaOS, Windows 3.x or early Apple. Or MS-DOS things like DESQview.
I fail to see the point - if you control the code and need performance so much that an occassional copy bites, you can as well just link it all into a single address space without those hoopjumps. It won't function as separate processes if it's modified to rely on passing pointers around anyway.
And if you don't, good luck chasing memory corruption issues.
Besides, what's wrong with shared memory?
Not negative at all, thanks for commenting. You're right that the answer is "nothing," and that this is a major trade-off inherent in the model. From a safety perspective, you'd need to be extremely confident that all threadprocs are well-behaved, though a memory-safe language would help some. The benefit is that you get process-like composition as separate binaries launched at separate times, with thread-like single-address space IPC.
After building this, I don't think this is necessarily a desirable trade-off, and decades of OS development certainly suggest process-isolated memory is desirable. I see this more as an experiment to see how bending those boundaries works in modern environments, rather than a practical way forward.