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From:   Daeho Jeong <daeho43@gmail.com>
Date:   Tue, 9 Mar 2021 22:00:40 +0900
Message-ID: <CACOAw_woQGgTy_hTfdcFufA7VG3cBVSN9vSD5bubvTeo+3wxsg@mail.gmail.com>
Subject: Re: [f2fs-dev] [PATCH v2] f2fs: add sysfs nodes to get accumulated
 compression info
To:     Chao Yu <yuchao0@huawei.com>
Cc:     linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net, kernel-team@android.com,
        Daeho Jeong <daehojeong@google.com>
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2021=EB=85=84 3=EC=9B=94 9=EC=9D=BC (=ED=99=94) =EC=98=A4=ED=9B=84 6:22, Ch=
ao Yu <yuchao0@huawei.com>=EB=8B=98=EC=9D=B4 =EC=9E=91=EC=84=B1:
>
> On 2021/3/5 10:24, Daeho Jeong wrote:
> > From: Daeho Jeong <daehojeong@google.com>
> >
> > Added acc_compr_inodes to show accumulated compressed inode count and
> > acc_compr_blocks to show accumulated secured block count with
>
> I noticed that these stat numbers are recorded in extra reserved area in
> hot node curseg journal, the journal will be persisted only for umount
> or fastboot checkpoint, so the numbers are not so accurate... does this
> satisfy your requirement?
>

Yes, we are satisfied with just getting rough number of them. But, it
would be better if you suggest more accurate way. :)

> > compression in sysfs. These can be re-initialized to "0" by writing "0"
> > value in one of both.
>
> Why do we allow reset the stat numbers?
>

Actually, I want to have a way to clear any stale number of them, but
I agree we don't need this.

> Why not covering all code with macro CONFIG_F2FS_FS_COMPRESSION, since th=
ese
> numbers are only be updated when we enable compression.
>

I wanted to keep the info even in the kernel with doesn't support
per-file compression if those had been written once. What do you
think?

> Thanks,