Hi Jaegeuk,
> -----Original Message-----
> From: linux-fsdevel-ow...@vger.kernel.org
> [mailto:linux-fsdevel-ow...@vger.kernel.org] On
> Behalf Of Jaegeuk Kim
> Sent: Wednesday, January 28, 2015 7:32 AM
> To: linux-ker...@vger.kernel.org; linux-fsde...@vger.kernel.org;
> linux-f2fs-devel@lists.sourceforge.net
> Cc: Jaegeuk Kim
> Subject: [PATCH 5/5] f2fs: introduce a batched trim
>
> This patch introduces a batched trimming feature, which submits split discard
> commands.
I didn't get it, why we should split discard commands. :(
Does smaller discarding for flash shows better performance or effect or safety?
Can you please explain more about this patch?
Thanks,
>
> Signed-off-by: Jaegeuk Kim <jaeg...@kernel.org>
> ---
> fs/f2fs/f2fs.h | 1 +
> fs/f2fs/segment.c | 15 ++++++++++-----
> 2 files changed, 11 insertions(+), 5 deletions(-)
>
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index c0b83d6..ec4d16b 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -104,6 +104,7 @@ enum {
> CP_DISCARD,
> };
>
> +#define BATCHED_TRIM_SEGMENTS 10
> struct cp_control {
> int reason;
> __u64 trim_start;
> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
> index 31c4e57..6c9c784 100644
> --- a/fs/f2fs/segment.c
> +++ b/fs/f2fs/segment.c
> @@ -1066,14 +1066,19 @@ int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct
> fstrim_range *range)
> end_segno = (end >= MAX_BLKADDR(sbi)) ? MAIN_SEGS(sbi) - 1 :
> GET_SEGNO(sbi, end);
> cpc.reason = CP_DISCARD;
> - cpc.trim_start = start_segno;
> - cpc.trim_end = end_segno;
> cpc.trim_minlen = range->minlen >> sbi->log_blocksize;
>
> /* do checkpoint to issue discard commands safely */
> - mutex_lock(&sbi->gc_mutex);
> - write_checkpoint(sbi, &cpc);
> - mutex_unlock(&sbi->gc_mutex);
> + for (; start_segno <= end_segno;
> + start_segno += BATCHED_TRIM_SEGMENTS + 1) {
> + cpc.trim_start = start_segno;
> + cpc.trim_end = min_t(unsigned int,
> + start_segno + BATCHED_TRIM_SEGMENTS, end_segno);
> +
> + mutex_lock(&sbi->gc_mutex);
> + write_checkpoint(sbi, &cpc);
> + mutex_unlock(&sbi->gc_mutex);
> + }
> out:
> range->len = cpc.trimmed << sbi->log_blocksize;
> return 0;
> --
> 2.1.1
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
> the body of a message to majord...@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
------------------------------------------------------------------------------
Dive into the World of Parallel Programming. The Go Parallel Website,
sponsored by Intel and developed in partnership with Slashdot Media, is your
hub for all things parallel software development, from weekly thought
leadership blogs to news, videos, case studies, tutorials and more. Take a
look and join the conversation now. http://goparallel.sourceforge.net/
_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
