Messages in this thread | | | Subject | Re: [f2fs-dev] [PATCH v6] f2fs: compress: support compress level | From | Chao Yu <> | Date | Fri, 4 Dec 2020 11:11:03 +0800 |
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On 2020/12/4 10:47, Gao Xiang wrote: > On Fri, Dec 04, 2020 at 10:38:08AM +0800, Chao Yu wrote: >> On 2020/12/4 10:06, Gao Xiang wrote: >>> On Fri, Dec 04, 2020 at 09:56:27AM +0800, Chao Yu wrote: > > ... > >> >>> >>> Keep lz4hc dirty data under writeback could block writeback, make kswapd >>> busy, and direct memory reclaim path, I guess that's why rare online >>> compression chooses it. My own premature suggestion is that it'd better >>> to show the CR or performance benefits in advance, and prevent unprivileged >>> users from using high-level lz4hc algorithm (to avoid potential system attack.) >>> either from mount options or ioctl. >> >> Yes, I guess you are worry about destop/server scenario, as for android scenario, >> all compression related flow can be customized, and I don't think we will use >> online lz4hc compress; for other scenario, except the numbers, I need to add the >> risk of using lz4hc algorithm in document. > > Yes, I was saying the general scenario. My overall premature thought is that > before releasing some brand new algorithm, it may be better to evaluate first > it'd benefit to some scenarios first (either on CR or performance side, or > why adding this?), or it would might cause lzo-rle likewise situation in the
Yeah, got your point.
> 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...
Thanks,
> https://lore.kernel.org/r/20201117223253.65920-1-alex_y_xu@yahoo.ca > (since I personally don't think BWT is a good algorithm as well)... Just FYI > ... If i'm wrong, kindly ignore me :) > > Thanks, > Gao Xiang > >> >> Thanks, > > . >
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