Date:   Sun, 29 Jan 2023 19:47:17 +0800
From:   qixiaoyu <qxy65535@gmail.com>
To:     Yangtao Li <frank.li@vivo.com>
Cc:     Jaegeuk Kim <jaegeuk@kernel.org>, Chao Yu <chao@kernel.org>,
        xiongping1@xiaomi.com, qixiaoyu1@xiaomi.com,
        linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net
Subject: Re: f2fs: set *_data_age_threshold according to user_block_count
Message-ID: <Y9ZcxUjQs4Hb0ZoT@mi-HP-ProDesk-680-G4-MT>
References: <20230117115702.GA12653@mi-HP-ProDesk-680-G4-MT>
 <20230117133814.79508-1-frank.li@vivo.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20230117133814.79508-1-frank.li@vivo.com>
Precedence: bulk

On Tue, Jan 17, 2023 at 09:38:14PM +0800, Yangtao Li wrote:
> Hi qixiaoyu,
> 
> > The block age here refers to total data blocks allocated of filesystem between two consecutive updates.
> 
> Yes, you are right.
> 
> > So, it has nothing to do with storage size.
> 
> But I think that the total data blocks allocated of filesystem between two consecutive updates
> has something to do with the storage size. For example, for a 60M f2fs image, the lifetime_write_kbytes
> will hardly reach 10G, or even 1G.
> 
> Thx,
> Yangtao

Hi Yangtao,

Block update frequency may related to applications and usage patterns,
not storage size. A 1G f2fs image may have a similar block age to a
10G f2fs image when running the same program.

So, it might not be a good idea to decide the *_data_age_threshold
based on user_block_count.

Thanks,