Re: [Qemu-devel] [PATCH v3 10/10] migration: show the statistics of compression

[Peter Xu <peterx@redhat.com>]

On Tue, Aug 07, 2018 at 05:12:09PM +0800, guangrong.xiao@gmail.com wrote:

[...]

> @@ -1602,6 +1614,26 @@ static void migration_update_rates(RAMState *rs, int64_t end_time)
>              rs->xbzrle_cache_miss_prev) / page_count;
>          rs->xbzrle_cache_miss_prev = xbzrle_counters.cache_miss;
>      }
> +
> +    if (migrate_use_compression()) {
> +        compression_counters.busy_rate = (double)(compression_counters.busy -
> +            rs->compress_thread_busy_prev) / page_count;

So this is related to the previous patch - I still doubt its
correctness if page_count is the host pages count rather than the
guest pages'.  Other than that the patch looks good to me.

Thanks,

> +        rs->compress_thread_busy_prev = compression_counters.busy;
> +
> +        compressed_size = compression_counters.compressed_size -
> +                          rs->compressed_size_prev;
> +        if (compressed_size) {
> +            double uncompressed_size = (compression_counters.pages -
> +                                    rs->compress_pages_prev) * TARGET_PAGE_SIZE;
> +
> +            /* Compression-Ratio = Uncompressed-size / Compressed-size */
> +            compression_counters.compression_rate =
> +                                        uncompressed_size / compressed_size;
> +
> +            rs->compress_pages_prev = compression_counters.pages;
> +            rs->compressed_size_prev = compression_counters.compressed_size;
> +        }
> +    }

-- 
Peter Xu