Subject: bug#26225: [PATCH] guix: Compress and decompress xz archives in parallel.

From: Leo Famulari <[email-masked]>
Date: Sun, 2 Apr 2017 17:21:18 -0400

On Sat, Apr 01, 2017 at 08:52:28AM +0200, Marius Bakke wrote:
> > Efraim Flashner wrote:
> >> * guix/scripts/pack.scm (%compressors): Add flag '-T0' when calling "xz".
> >> * guix/utils.scm (decompressed-port, compressed-port,
> >> compressed-output-port): Same.
> >
> >> --- a/guix/utils.scm
> >> +++ b/guix/utils.scm
> >> @@ -154,7 +155,7 @@ a symbol such as 'xz."
> >>    (match compression
> >>      ((or #f 'none) (values input '()))
> >>      ('bzip2        (filtered-port `(,%bzip2 "-dc") input))
> >> -    ('xz           (filtered-port `(,%xz "-dc") input))
> >> +    ('xz           (filtered-port `(,%xz "-dc -T0") input))
> >>      ('gzip         (filtered-port `(,%gzip "-dc") input))
> >>      (else          (error "unsupported compression scheme" compression))))
> 
> Is (parallel-job-count) accessible here? It would be nice to respect it.

I agree, it would be good if we respected it here, if possible.