On 2020/11/3 16:38, Daejun Park wrote:
In the fs-based mode of F2FS, the mapping of hot/warm node to
WRITE_LIFE_NOT_SET should be changed to WRITE_LIFE_SHORT.
As a result of analyzing the write pattern of f2fs using real workload,
hot/warm nodes have high update ratio close to hot data.[*]
However, F2FS passes write hints for hot/warm nodes as WRITE_LIFE_NOT_SET.
Furthermore, WRITE_LIFE_NOT_SET is a default value of write hint when it is
not provided from the file system.
In storage, write_hint is used to distinguish streams (e.g. NVMe).
So, the hot/warm node of F2FS is not distinguished from other write_hints,
which can make the wrong stream seperation.
* Liang, Yu, et al. "An empirical study of F2FS on mobile devices." 2017
IEEE 23rd International Conference on Embedded and Real-Time Computing
Systems and Applications (RTCSA).
Signed-off-by: Daejun Park <daejun7.p...@samsung.com>
Reviewed-by: Chao Yu <yuch...@huawei.com>
Thanks,
