Re: [PATCHv3 3/8] zram: remove good and bad compress stats

Jerome Marchand
2014-01-16T13:45:08Z

On 01/16/2014 02:12 PM, Sergey Senozhatsky wrote:
> Remove `good' and `bad' compressed sub-requests stats. RW request may
> cause a number of RW sub-requests. zram used to account `good' compressed
> sub-queries (with compressed size less than 50% of original size), `bad'
> compressed sub-queries (with compressed size greater that 75% of original
> size), leaving sub-requests with compression size between 50% and 75% of
> original size not accounted and not reported. zram already accounts each
> sub-request's compression size so we can calculate real device compression
> ratio.
>
> Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Jerome Marchand <jmarchan@redhat.com>

> ---
> drivers/block/zram/zram_drv.c | 11 -----------
> drivers/block/zram/zram_drv.h | 2 --
> 2 files changed, 13 deletions(-)
>
> diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
> index b0bcb7e..c7c7789 100644
> --- a/drivers/block/zram/zram_drv.c
> +++ b/drivers/block/zram/zram_drv.c
> @@ -293,7 +293,6 @@ static void zram_free_page(struct zram *zram, size_t index)
> {
> struct zram_meta *meta = zram->meta;
> unsigned long handle = meta->table[index].handle;
> - u16 size = meta->table[index].size;
>
> if (unlikely(!handle)) {
> /*
> @@ -307,14 +306,8 @@ static void zram_free_page(struct zram *zram, size_t index)
> return;
> }
>
> - if (unlikely(size > max_zpage_size))
> - atomic_dec(&zram->stats.bad_compress);
> -
> zs_free(meta->mem_pool, handle);
>
> - if (size <= PAGE_SIZE / 2)
> - atomic_dec(&zram->stats.good_compress);
> -
> atomic64_sub(meta->table[index].size, &zram->stats.compr_size);
> atomic_dec(&zram->stats.pages_stored);
>
> @@ -478,7 +471,6 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
> }
>
> if (unlikely(clen > max_zpage_size)) {
> - atomic_inc(&zram->stats.bad_compress);
> clen = PAGE_SIZE;
> src = NULL;
> if (is_partial_io(bvec))
> @@ -518,9 +510,6 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
> /* Update stats */
> atomic64_add(clen, &zram->stats.compr_size);
> atomic_inc(&zram->stats.pages_stored);
> - if (clen <= PAGE_SIZE / 2)
> - atomic_inc(&zram->stats.good_compress);
> -
> out:
> if (locked)
> mutex_unlock(&meta->buffer_lock);
> diff --git a/drivers/block/zram/zram_drv.h b/drivers/block/zram/zram_drv.h
> index e81e9cd..2f173cb 100644
> --- a/drivers/block/zram/zram_drv.h
> +++ b/drivers/block/zram/zram_drv.h
> @@ -78,8 +78,6 @@ struct zram_stats {
> atomic64_t notify_free; /* no. of swap slot free notifications */
> atomic_t pages_zero; /* no. of zero filled pages */
> atomic_t pages_stored; /* no. of pages currently stored */
> - atomic_t good_compress; /* % of pages with compression ratio<=50% */
> - atomic_t bad_compress; /* % of pages with compression ratio>=75% */
> };
>
> struct zram_meta {
>