Re: Very slow download speed of substitutes

["Ludovic Courtès" <ludo@gnu.org>]

Hi,

Lo Peter <peterloleungyau@gmail.com> skribis:

> I am trying guix import from cran, and building some R packages, which
> sometimes needs to download substitutes. i noticed that the download
> speed can be ridiculously slow and seems especially during night in
> HKT.
>
> Here is a snippet of the downloading:
>
> substituting /gnu/store/njhd9w4pvp2c6mbdngg1xvvld82a2c1l-ghc-ansi-wl-pprint-0.6.9...
> downloading from
> https://ci.guix.gnu.org/nar/lzip/njhd9w4pvp2c6mbdngg1xvvld82a2c1l-ghc-ansi-wl-pprint-0.6.9
> ...
>  ghc-ansi-wl-pprint-0.6.9  123KiB            25KiB/s 00:05
> [##################] 100.0%
>
> substituting /gnu/store/p035ilg1b6ywpxxj8df494x8zxnnwg12-ghc-data-default-instances-containers-0.0.1...
> downloading from
> https://ci.guix.gnu.org/nar/lzip/p035ilg1b6ywpxxj8df494x8zxnnwg12-ghc-data-default-instances-containers-0.0.1
> ...
>  ghc-data-default-instances-containers-0.0.1  42KiB 37KiB/s 00:01
> [##################] ghc-data-default-instances-containers-0.0.1
> 42KiB 37KiB/s 00:01 [##################] 100.0%

These are all small files so the download speed that is displayed may be
inaccurate.  I’d encourage you to check and report the download speed
for large files, say LibreOffice.

That said, the code in Guix could be improved by arranging to keep the
HTTPS connection alive between downloads instead of reopening it every
time.  This is especially expensive when downloading lots of small files
as is the case above.

Thanks,
Ludo’.