Re: Bash-specific performance by avoiding sed

[Richard Purdie]

On Mon, 2015-03-09 at 18:28 +0000, Mike Gran wrote:
> I don't know if y'all saw this blogpost where a guy pushed
> the sed regular expression handling into bash-specific
> regular expressions when bash was available.  He claims
> there's a significant performance improvement because of
> reduced forking.
> 
> http://harald.hoyer.xyz/2015/03/05/libtool-getting-rid-of-180000-sed-forks/

Please see my reply about this. The issue is the amount of looping
through the options parsing code which I did already report here as an
issue.

I do have a "fix" for it in the build systems I look after:

http://git.yoctoproject.org/cgit.cgi/poky/commit/?id=cc5f804483a9a1a60be24475baee0eed5d44bef5

which basically unrolls some of the internal code looping and I believe
that with that patch, the speedup to the specific sed invocation you're
looking at will be much less relevant.

The issue is that in its current form, it can't really be merged and my
shell knowledge and lack of contribution agreement to GNU are likely
blocking issues along with a lack of time :(

Cheers,

Richard