Re: [f2fs-dev] [PATCH 1/3] f2fs: use f2fs_submit_page_bio for ra_meta_pages

From: Chao Yu
Date: Wed May 10 2017 - 21:47:57 EST


On 2017/5/11 9:24, Chao Yu wrote:
> Hi Jaegeuk,
>
> On 2017/5/11 7:48, Jaegeuk Kim wrote:
>> This patch avoids to use f2fs_submit_merged_bio for read, which was the only
>> read case.
>
> This makes f2fs losing the chance to merge multiple pages into one bio during
> reading continuous physical blocks, it may cause potential performance
> regression, how about using a local bio in ra_meta_pages to cache more pages?

BTW, need to remove sbi->read_io as well?

Thanks,

>
> Thanks,
>
>>
>> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
>> ---
>> fs/f2fs/checkpoint.c | 4 +---
>> 1 file changed, 1 insertion(+), 3 deletions(-)
>>
>> diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
>> index ea9c317b5916..8d92f8249000 100644
>> --- a/fs/f2fs/checkpoint.c
>> +++ b/fs/f2fs/checkpoint.c
>> @@ -207,12 +207,10 @@ int ra_meta_pages(struct f2fs_sb_info *sbi, block_t start, int nrpages,
>> }
>>
>> fio.page = page;
>> - fio.old_blkaddr = fio.new_blkaddr;
>> - f2fs_submit_page_mbio(&fio);
>> + f2fs_submit_page_bio(&fio);
>> f2fs_put_page(page, 0);
>> }
>> out:
>> - f2fs_submit_merged_bio(sbi, META, READ);
>> blk_finish_plug(&plug);
>> return blkno - start;
>> }
>>
>
>
> .
>