vfork() (was Re: RS6000 questions/comments)

[Theo de Raadt]

In article <19439 at rpp386.cactus.org> jfh at rpp386.cactus.org (John F Haugh II) writes:
> I don't know what you call "particularly efficient", but I have measured
> fork/exit performance and AIX v3 is worse than SVR1 on a 12MHz 68000 that
> I tested in 1986.  As I recall a S/6000 Model 530 produced about 8 or 10
> fork/exits per second, compared to about 45 per second on an Mpulse/XL
> that I was testing for my employer in 1986 (Pinnacle Systems, Inc.,
> Garland TX)
> The test is real simple -
>  main ()
>  {
>  int i;
>
>      for (i = 0;i < 10000;i++)
>          if (fork () == 0)
>              exit ();
>          else
>              while (wait (0) != -1)
>                  ;
>   }

I'll bite and shove a vfork() in there instead of fork(). Here are
times for a Sun4/490, sunos4.1.1.

 fork()      101.1 real         5.6 user        90.2 sys	  99  fork/sec
vfork()        9.7 real         0.5 user         6.5 sys	1030 vfork/sec

I suggest those who say that vfork() is not needed anymore try this test
on their machine.
 <tdr.

--

SunOS 4.1.1: /usr/include/vm/as.h, Line 49    | Theo de Raadt
typo? Should the '_'  be an 's'??             | deraadt at cpsc.ucalgary.ca