Pay as you go is really going to make a difference

Fri Jan 24 20:29:36 UTC 2020

On 2020-01-24 10:52, Johan Engelen wrote:

> Indeed. Also to figure out why LDC's binary calls 31 more than DMD's 
> binary.
> Much appreciated if someone could repeat the test and post a list of all 
> syscalls being made.

Not exactly the same as the original post, but here's some data I pulled 
out for macOS 10.14.6 with a Hello World compiled with DMD 2.088.0. This 
should give somewhat of an idea what's going on in the application. I've 
included the stacktrace for all syscalls NOT made by the system.

As you can see below, 10 calls are made by the application, all of the 
remaining calls are made by the system itself. Most of the calls made by 
the system are made by the dynamic loader. Only three calls originate 
from the D main function. Only one call into the C standard library is 
made from the D main function, which is the call to `fwrite`.

It's not our fault that the system does so many calls :).

total: 120, system: 110, app: 10

stat64, total: 40, system: 40, app: 0

-----------------------------------------------

mach_vm_map_trap, total: 8, system: 6, app: 2

    6 libsystem_malloc.dylib malloc
    7 foobar 
_D2rt5minfo11ModuleGroup9sortCtorsMFAyaZ6doSortMFmKAPyS6object10ModuleInfoZb
    8 foobar _D2rt5minfo11ModuleGroup9sortCtorsMFAyaZv
    9 foobar _D2rt5minfo11ModuleGroup9sortCtorsMFZv
   10 foobar 
_D2rt5minfo13rt_moduleCtorUZ14__foreachbody1MFKSQBu19sections_osx_x86_6412SectionGroupZi
   11 foobar rt_moduleCtor
   12 foobar rt_init
   13 foobar _D2rt6dmain212_d_run_main2UAAamPUQgZiZ6runAllMFZv
   14 foobar _D2rt6dmain212_d_run_main2UAAamPUQgZiZ7tryExecMFMDFZvZv
   15 foobar _d_run_main2
   16 foobar _d_run_main
   17 foobar main
   18 libdyld.dylib start

   10 libsystem_c.dylib fwrite
   11 foobar 
_D3std5stdio__T13trustedFwriteTaZQsFNbNiNePOS4core4stdcQBx7__sFILExAaZm 
~/.dvm/compilers/dmd-2.088.0/osx/bin/../../src/phobos/std/stdio.d:4322
   12 foobar _D3std5stdio4File17LockingTextWriter__T3putTAyaZQjMFNfMQlZv 
~/.dvm/compilers/dmd-2.088.0/osx/bin/../../src/phobos/std/stdio.d:2930
   13 foobar _D3std5stdio__T7writelnTAyaZQnFNfQjZv 
~/.dvm/compilers/dmd-2.088.0/osx/bin/../../src/phobos/std/stdio.d:3855
   14 foobar _Dmain ~/development/d/main.d:15
   15 foobar _D2rt6dmain212_d_run_main2UAAamPUQgZiZ6runAllMFZ9__lambda1MFZv
   16 foobar _D2rt6dmain212_d_run_main2UAAamPUQgZiZ7tryExecMFMDFZvZv
   17 foobar _D2rt6dmain212_d_run_main2UAAamPUQgZiZ6runAllMFZv
   18 foobar _D2rt6dmain212_d_run_main2UAAamPUQgZiZ7tryExecMFMDFZvZv
   19 foobar _d_run_main2
   20 foobar _d_run_main
   21 foobar main
   22 libdyld.dylib start

-----------------------------------------------
mprotect, total: 8, system: 8
mach_port_deallocate_trap, total: 4, system: 4
-----------------------------------------------
sigaction, total: 4, system: 0, app: 4

    0 libsystem_kernel.dylib __sigaction
    1 libsystem_platform.dylib __platform_sigaction
    2 foobar runModuleUnitTests
    3 foobar _D2rt6dmain212_d_run_main2UAAamPUQgZiZ6runAllMFZv
    4 foobar _D2rt6dmain212_d_run_main2UAAamPUQgZiZ7tryExecMFMDFZvZv
    5 foobar _d_run_main2
    6 foobar _d_run_main
    7 foobar main
    8 libdyld.dylib start

-----------------------------------------------
mach_reply_port, total: 4, system: 4, app: 0
host_self_trap, total: 3, system: 3, app: 0
mach_port_mod_refs_trap, total: 3, system: 3, app: 0
ioctl, total: 3, system: 3, app: 0
mach_port_construct_trap, total: 3, system: 3, app: 0
kdebug_typefilter, total: 2, system: 2, app: 0
thread_self_trap, total: 2, system: 2, app: 0
proc_info, total: 2, system: 2, app: 0
mach_port_destruct_trap, total: 2, system: 2, app: 0
csops, total: 2, system: 2, app: 0
getpid, total: 2, system: 2, app: 0
task_self_trap, total: 2, system: 2, app: 0
access, total: 1, system: 1, app: 0
close, total: 1, system: 1, app: 0
shared_region_check_np, total: 1, system: 1, app: 0
-------------------------------------------------------
fstat64, total: 1, system: 0, app: 1

    5 libsystem_c.dylib fwrite
    6 foobar 
_D3std5stdio__T13trustedFwriteTaZQsFNbNiNePOS4core4stdcQBx7__sFILExAaZm 
~/.dvm/compilers/dmd-2.088.0/osx/bin/../../src/phobos/std/stdio.d:4322
    7 foobar _D3std5stdio4File17LockingTextWriter__T3putTAyaZQjMFNfMQlZv 
~/.dvm/compilers/dmd-2.088.0/osx/bin/../../src/phobos/std/stdio.d:2930
    8 foobar _D3std5stdio__T7writelnTAyaZQnFNfQjZv 
~/.dvm/compilers/dmd-2.088.0/osx/bin/../../src/phobos/std/stdio.d:3855
    9 foobar _Dmain ~/development/d/main.d:15
   10 foobar _D2rt6dmain212_d_run_main2UAAamPUQgZiZ6runAllMFZ9__lambda1MFZv
   11 foobar _D2rt6dmain212_d_run_main2UAAamPUQgZiZ7tryExecMFMDFZvZv
   12 foobar _D2rt6dmain212_d_run_main2UAAamPUQgZiZ6runAllMFZv
   13 foobar _D2rt6dmain212_d_run_main2UAAamPUQgZiZ7tryExecMFMDFZvZv
   14 foobar _d_run_main2
   15 foobar _d_run_main
   16 foobar main
   17 libdyld.dylib start

-----------------------------------------------
mac_vm_allocate_trap, total: 1, system: 1, app: 0
open, total: 1, system: 1, app: 0
mac_syscall, total: 1, system: 1, app: 0
-----------------------------------------------
sysctl, total: 1, system: 0, app: 1

    3 libsystem_c.dylib sysconf
    4 foobar _D4core6thread26_sharedStaticCtor_L3685_C1FZv
    5 foobar _D4core6thread15__modsharedctorFZv
    6 foobar 
_D2rt5minfo__T14runModuleFuncsSQBdQBd11ModuleGroup8runCtorsMFZ9__lambda2ZQChMFAxPyS6object10ModuleInfoZv
    7 foobar _D2rt5minfo11ModuleGroup8runCtorsMFZv
    8 foobar 
_D2rt5minfo13rt_moduleCtorUZ14__foreachbody1MFKSQBu19sections_osx_x86_6412SectionGroupZi
    9 foobar rt_moduleCtor
   10 foobar rt_init
   11 foobar _D2rt6dmain212_d_run_main2UAAamPUQgZiZ6runAllMFZv
   12 foobar _D2rt6dmain212_d_run_main2UAAamPUQgZiZ7tryExecMFMDFZvZv
   13 foobar _d_run_main2
   14 foobar _d_run_main
   15 foobar main
   16 libdyld.dylib start

-----------------------------------------------
getentropy, total: 1, system: 1, app: 0
issetugid, total: 1, system: 1, app: 0
bsdthread_register, total: 1, system: 1, app: 0

-----------------------------------------------
write_nocancel, total: 1, system: 0, app: 1

    0 libsystem_kernel.dylib __write_nocancel
    1 libsystem_c.dylib _swrite
    2 libsystem_c.dylib __sflush
    3 libsystem_c.dylib fflush
    4 foobar _d_run_main2
    5 foobar _d_run_main
    6 foobar main
    7 libdyld.dylib start

-----------------------------------------------
exit, total: 1, system: 1, app: 0

-----------------------------------------------
getrlimit, total: 1, system: 0, app: 1

    8 libsystem_c.dylib fwrite
    9 foobar 
_D3std5stdio__T13trustedFwriteTaZQsFNbNiNePOS4core4stdcQBx7__sFILExAaZm 
~/.dvm/compilers/dmd-2.088.0/osx/bin/../../src/phobos/std/stdio.d:4322
   10 foobar _D3std5stdio4File17LockingTextWriter__T3putTAyaZQjMFNfMQlZv 
~/.dvm/compilers/dmd-2.088.0/osx/bin/../../src/phobos/std/stdio.d:2930
   11 foobar _D3std5stdio__T7writelnTAyaZQnFNfQjZv 
~/.dvm/compilers/dmd-2.088.0/osx/bin/../../src/phobos/std/stdio.d:3855
   12 foobar _Dmain ~/development/d/main.d:15
   13 foobar _D2rt6dmain212_d_run_main2UAAamPUQgZiZ6runAllMFZ9__lambda1MFZv
   14 foobar _D2rt6dmain212_d_run_main2UAAamPUQgZiZ7tryExecMFMDFZvZv
   15 foobar _D2rt6dmain212_d_run_main2UAAamPUQgZiZ6runAllMFZv
   16 foobar _D2rt6dmain212_d_run_main2UAAamPUQgZiZ7tryExecMFMDFZvZv
   17 foobar _d_run_main2
   18 foobar _d_run_main
   19 foobar main
   20 libdyld.dylib start

-----------------------------------------------
mach_timebase_info, total: 1, system: 1, app: 0
sysctlbyname, total: 1, system: 1, app: 0
csrctl, total: 1, system: 1, app: 0
thread_selfid, total: 1, system: 1, app: 0

-- 
/Jacob Carlborg