Re: [f2fs-dev] [PATCH] f2fs: include non-compressed blocks in compr_written_block

[Chao Yu]

On 2021/10/12 0:02, Daeho Jeong wrote:
> > > diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
> > > index c1bf9ad4c220..9b663eaf4805 100644
> > > --- a/fs/f2fs/compress.c
> > > +++ b/fs/f2fs/compress.c
> > > @@ -1530,6 +1530,7 @@ int f2fs_write_multi_pages(struct compress_ctx *cc,
> > >        if (cluster_may_compress(cc)) {
> > >                err = f2fs_compress_pages(cc);
> > >                if (err == -EAGAIN) {
> > > +                     add_compr_block_stat(cc->inode, cc->cluster_size);
> >
> > Shouldn't we relocate this after 'write' label?
> >
> > One more concern, it looks we've changed what compr_block stat indicated,
> > literally, the block we account should be compressed..., how about accounting
> > it by introducing .presist_blocks, used_blocks or occupied_blocks.... thoughts?
>
> What I wanted to add here is just one case in which compression was
> tried, but couldn't save any block, so gave up.
> If we put this below the "write" label, we will count blocks, even if
> the file is turned off for compression in "user-controlled
> compression" mode.
> Like the commit comment says, I want to estimate the overall compression rate.
> But, if we include every other compression disabled condition, it
> won't work like that.

Got it, thanks for the explanation.

Any thoughts about renaming compr_block? since some blocks accounted in
.compr_block weren't compressed blocks.

Thanks,

> Thanks,