Re: [f2fs-dev] [PATCH v6] f2fs: compress: support compress level

Gao Xiang
2020-12-04T03:23:22Z

On Fri, Dec 04, 2020 at 11:11:03AM +0800, Chao Yu wrote:
> On 2020/12/4 10:47, Gao Xiang wrote:

...

>
> > future (and add more dependency to algorithms, you might see BWT-based bzip2
> > removal patch
>
> Oops, is that really allowed? I don't this is a good idea...and I don't see there
> are deletions from fs/ due to similar reason...

Fortunately, bzip is quite slow algorithm, so not affective at all.

My personal opinion based on compress algorithm principle (just for reference
as well...)
- zlib should be better replaced with libdeflate if possible, the main point
is that many hardware accelerator for deflate (LZ77 + huffman) are
available;

- lzo is not attractive from its format complexity and its CR/performance
goal so lz4 is generally better due to its format design;

- lzo-rle, oops, just introduced for zram I think, not sure quite helpful
for file data (since anonymous pages are generally RLE-effective due to
many repeative data.) But it'd be good if lzo author accepts it.

Thanks,
Gao Xiang

>
> Thanks,
> >
>