This change also removes the futimens() call on the Landlock Make output
file workaround, since it caused problems with commands like fixupobj
which modify-in-place. It turns out if a file is opened for writing and
then no writes actually occur, then the modified time doesn't change.
- 10.5% reduction of o//depend dependency graph
- 8.8% reduction in latency of make command
- Fix issue with temporary file cleanup
There's a new -w option in compile.com that turns off the recent
Landlock output path workaround for "good commands" which do not
unlink() the output file like GNU tooling does.
Our new GNU Make unveil sandboxing appears to have zero overhead
in the grand scheme of things. Full builds are pretty fast since
the only thing that's actually slowed us down is probably libcxx
make -j16 MODE=rel
RL: took 85,732,063µs wall time
RL: ballooned to 323,612kb in size
RL: needed 828,560,521µs cpu (11% kernel)
RL: caused 39,080,670 page faults (99% memcpy)
RL: 350,073 context switches (72% consensual)
RL: performed 0 reads and 11,494,960 write i/o operations
pledge() and unveil() no longer consider ENOSYS to be an error.
These functions have also been added to Python's cosmo module.
This change also removes some WIN32 APIs and System Five magnums
which we're not using and it's doubtful anyone else would be too
I wanted a tiny scriptable meltdown proof way to run userspace programs
and visualize how program execution impacts memory. It helps to explain
how things like Actually Portable Executable works. It can show you how
the GCC generated code is going about manipulating matrices and more. I
didn't feel fully comfortable with Qemu and Bochs because I'm not smart
enough to understand them. I wanted something like gVisor but with much
stronger levels of assurances. I wanted a single binary that'll run, on
all major operating systems with an embedded GPL barrier ZIP filesystem
that is tiny enough to transpile to JavaScript and run in browsers too.
https://justine.storage.googleapis.com/emulator625.mp4
