Re: [PATCH 3/3] f2fs: provide more chance for node and data to get ssr segment

From: Yunlong Song
Date: Wed Feb 22 2017 - 21:44:25 EST


Hi Jay,
I miss some codes from your mail, now I check all your patch codes and make clear with question 2 and 3, it's fine.

But still, how about question 1?

On 2017/2/23 10:13, Yunlong Song wrote:
> Hi Jay,
> But there are some differences:
> 1 Why not take "neighboring temperature" for ssr? For example, if type == CURSEG_COLD_DATA,
> your new patch selects CURSEG_HOT_DATA first, how about select CURSEG_WARM_DATA first?
> The patch I sent ensure this "neighboring temperature" for ssr.
> 2 Your new patch returns 0 for node ssr, does get_ssr_segment work only for data?
> 3 I see your new patch just "continue" when i == type, why not consider the current type?
>
> On 2017/2/23 9:17, Jaegeuk Kim wrote:
>> Hi Yunlong,
>>
>> I've been testing the similar patches as I attached.
>>
>> Thanks,
>>
>> On 02/22, Yunlong Song wrote:
>>> Signed-off-by: Yunlong Song <yunlong.song@xxxxxxxxxx>
>>> ---
>>> fs/f2fs/segment.c | 9 +++++++++
>>> 1 file changed, 9 insertions(+)
>>>
>>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
>>> index 9d13743..5fe71b9 100644
>>> --- a/fs/f2fs/segment.c
>>> +++ b/fs/f2fs/segment.c
>>> @@ -1540,12 +1540,17 @@ static int get_ssr_segment(struct f2fs_sb_info *sbi, int type)
>>> {
>>> struct curseg_info *curseg = CURSEG_I(sbi, type);
>>> const struct victim_selection *v_ops = DIRTY_I(sbi)->v_ops;
>>> + int old_type = type;
>>>
>>> if (IS_NODESEG(type)) {
>>> for (; type >= CURSEG_HOT_NODE; type--)
>>> if (v_ops->get_victim(sbi, &(curseg)->next_segno,
>>> BG_GC, type, SSR))
>>> return 1;
>>> + for (type = old_type + 1; type <= CURSEG_COLD_NODE; type++)
>>> + if (v_ops->get_victim(sbi, &(curseg)->next_segno,
>>> + BG_GC, type, SSR))
>>> + return 1;
>>> return 0;
>>> }
>>>
>>> @@ -1554,6 +1559,10 @@ static int get_ssr_segment(struct f2fs_sb_info *sbi, int type)
>>> if (v_ops->get_victim(sbi, &(curseg)->next_segno,
>>> BG_GC, type, SSR))
>>> return 1;
>>> + for (type = old_type + 1; type <= CURSEG_COLD_DATA; type++)
>>> + if (v_ops->get_victim(sbi, &(curseg)->next_segno,
>>> + BG_GC, type, SSR))
>>> + return 1;
>>> return 0;
>>> }
>>>
>>> --
>>> 1.8.5.2
>


--
Thanks,
Yunlong Song