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

[Chao Yu]

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?

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;
>  }
>