redo: 5.4s
redo -j4: 3.0s
make: 2.3s
make -j4: 1.4s
make SHELL=/bin/dash: 1.2s
make SHELL=/bin/dash -j4: 0.83s
We have some distance to go yet. Of course, redo is still written in
python, not C, so it's very expensive, and the on-disk dependency store is
very inefficient.
Now t/curse passes again when parallelized (except for the countall
mismatch, since we haven't fixed the source of that problem yet). At least
it's consistent now.
There's a bunch of stuff rearranged in here, but the actual important
problem was that we were doing unlink() on the lock fifo even if ENXIO,
which meant a reader could connect in between ENXIO and unlink(), and thus
never get notified of the disconnection. This would cause the build to
randomly freeze.
...because it seems my locking isn't very good. It exposes annoying
problems involving rebuilding the same files more than once, screwing up
stamp files with redo -j, and being unnecessarily slow when checking
dependencies. So it's a pretty good test considering how simple it is.
Didn't add it to t/all.do yet, because it would fail.
This could be good for distributing with your packages, so that people who
don't have redo installed can at least build it. Also, we could use it for
building redo itself.
Will surely need to get slightly bigger as I inevitably discover I've
forgotten a critical feature.
This is a departure from how djb seems to have it set up, but I just like it
better. It's more like the reasonably-common Makefile standard. (Although
what make *actually* does is just use the first target declared in the
file.)
I'm pretty sure this must be the intended behaviour. It's kind of
meaningless to use this to declare a dependency on a file that might start
to exist later, if the file already exists.
'./redo -d test' reveals that we check and re-check things like CC and LD
even when they're children of objects that don't need to be rebuilt, and who
we've already checked earlier in the build cycle. We need to be a little
smarter about pruning if we want dependency checking to be fast.
And move test scripts into t/ subdir to keep things clean.
As part of that, make sure redo adds itself to the PATH on startup so that
subscripts can find it.
