maria-discuss team mailing list archive

[Peter Laursen <peter_laursen@xxxxxxxxxx>]

Your 3rd test case takes 2:02 in MariaDB 10.1 and 2:13 in MySQL 5.6 on my
system (when otherwise idle) .

-- Peter

On Tue, Mar 3, 2015 at 1:58 PM, Federico Razzoli <federico_raz@xxxxxxxx>
wrote:

> I made some quick test to show what I mean by "performance problem". Note
> that I'm not saying the the first and the second test cases should perform
> equally. But there is too much difference - see the conclusion.
>
> 1)
>
> MariaDB [test]> SELECT BENCHMARK(50000000, (SELECT 1));
> +---------------------------------+
> | BENCHMARK(50000000, (SELECT 1)) |
> +---------------------------------+
> |                               0 |
> +---------------------------------+
> 1 row in set (0.42 sec)
>
> 2)
>
> DELIMITER ||
> CREATE FUNCTION f()
>         RETURNS TINYINT
> BEGIN
>         RETURN 1;
> END ||
> DELIMITER ;
>
> MariaDB [test]> SELECT BENCHMARK(50000000, (SELECT f()));
> +-----------------------------------+
> | BENCHMARK(50000000, (SELECT f())) |
> +-----------------------------------+
> |                                 0 |
> +-----------------------------------+
> 1 row in set (2 min 5.70 sec)
>
> 3)
>
> DELIMITER ||
> CREATE FUNCTION f(x TINYINT)
>         RETURNS TINYINT
> BEGIN
>         RETURN x;
> END ||
> DELIMITER ;
>
> MariaDB [test]> SELECT BENCHMARK(50000000, (SELECT f(1)));
> +------------------------------------+
> | BENCHMARK(50000000, (SELECT f(1))) |
> +------------------------------------+
> |                                  0 |
> +------------------------------------+
> 1 row in set (3 min 35.20 sec)
>
> -- Conclusions:
>
> Times in seconds:
>
> 0.42
> 125.70
> 215.20
>
> I don't know which ratio would be acceptable, but the difference betweem a
> trivial query and a trivial function is too high.
> Also, the difference between 2) and 3) is that the function in 3) accepts
> and returns a parameter. Again, the performance difference seems to me too
> high.
>
> Regards
> Federico
>
>
>
>
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