Hi Ævar, On Tue, 3 Apr 2018, Ævar Arnfjörð Bjarmason wrote: > [...] I think it would be really interesting to see the third > approach I suggested, i.e. hack the shell to make the test_cmp a builtin > and test that. Then you won't fork, but will get the advantage of your > fast C codepath. That should be relatively equivalent to running in BusyBox-w32's ash. BusyBox-w32 is a pure-Win32 version of BusyBox (i.e. it does not use any POSIX emulation layer, not Cygwin nor MSYS2). I did not notice any Earth-shaking performance improvement when running a test with BusyBox-w32's ash. It was a couple of percent, maybe even 20% faster, but nowhere near the orders of magnitude I had been expecting. > Also, even if test_cmp is much faster, Peff's results over at > https://public-inbox.org/git/20161020123111.qnbsainul2g54z4z@sigill.intra.peff.net/ > suggest that you may not notice anyway. Aside from the points raised > there about the bin wrappers it seems the easiest wins are having a > builtin version of "rm" and "cat". In BusyBox-w32, `rm` and `cat` *are* built-ins. > Are you able to compile dash on Windows with some modification of the > patch I sent upthread? In theory, yes. In practice, I lack the time (and I do not expect this to have any performance benefit over using BusyBox-w32 to run the test suite). Ciao, Dscho