Re: [PATCH v3 3/8] lib: add zstd support to decompress

From: Petr Malat
Date: Thu Mar 26 2020 - 12:47:48 EST


Hi!
On Wed, Mar 25, 2020 at 12:58:44PM -0700, Nick Terrell wrote:
> From: Nick Terrell <terrelln@xxxxxx>
> * Add unzstd() and the zstd decompress interface.
Here I do not understand why you limit the window size to 8MB even when
you read a larger value from the header. I do not see a reason why there
should be such a limitation at the first place and if there should be,
why it differs from ZSTD_WINDOWLOG_MAX.

I removed that limitation to be able to test it in my environment and I
found the performance is worst than with my patch by roughly 20% (on
i7-3520M), which is a major drawback considering the main motivation
to use zstd is the decompression speed. I will test on arm as well and
share the result tomorrow.
Petr