[OE-core] [PATCH v4 2/2] image_types: add Zstandard conversion support

[Alex Kiernan]

On Wed, Nov 20, 2019 at 10:32 AM Adrian Bunk <bunk at stusta.de> wrote:
>
> On Wed, Nov 20, 2019 at 09:12:58AM +0000, Stefan Agner wrote:
> >...
> > --- a/meta/classes/image_types.bbclass
> > +++ b/meta/classes/image_types.bbclass
> > @@ -59,6 +59,8 @@ XZ_INTEGRITY_CHECK ?= "crc32"
> >
> >  ZIP_COMPRESSION_LEVEL ?= "-9"
> >
> > +ZSTD_COMPRESSION_LEVEL ?= "-3"
> > +
> >...
>
> Why -3 and not -19 ?
>
> Compression speed is not a real issue, and AFAIR decompression
> tends to be slightly faster with smaller compressed size.
> Plus the benefit that smaller images are faster to load
> from network/storage.
>

I've been carrying similar functionality locally and at some point
pushed to `--ultra -22` and with a large image (~2GiB) the compression
stage then took literally hours. Not sure I tested with `-19` though

-- 
Alex Kiernan