Re: RFC: import of posix_spawn GSoC results

[yamt%mwd.biglobe.ne.jp@localhost (YAMAMOTO Takashi)]

hi,

> I updated my patches after fixing a sever bug that caused fallout in lots
> of (apparently unrelated) atf tests by fooling ld.elf_so into insecure
> mode, thus not allowing LD_PRELOAD and breaking all the rump clients...
> 
>    ftp.netbsd.org:/pub/NetBSD/misc/martin/posix_spawn/newfiles_20120125.tar.gz
>    
> ftp.netbsd.org:/pub/NetBSD/misc/martin/posix_spawn/posix_spawn_20120125.diff.gz

is it safe to release exec_lock? 

YAMAMOTO Takashi

> 
> I have been unable to find any statistically valid performance differences,
> either between posix_spawn and vfork, nor between execv* on a patched vs.
> an unpatched kernel - it is all in the sub-prommille range within a few
> percent noise.
> 
> A working alternative aproach to this patch is to use a vfork based emulation
> in userland only (FreeBSD is doing that). It is less kernel code, but to
> me sounds a bit hackish and/or fragile - maybe a matter of personal taste.
> 
> I will ask core which of the two variants we want to go with.
> 
> Martin