[ping][PATCH] Separate benchmarks for fast and slow paths of pow and exp

[Siddhesh Poyarekar <siddhesh@redhat.com>]

Ping!

On Wed, Mar 20, 2013 at 04:10:00PM +0530, Siddhesh Poyarekar wrote:
> Hi,
> 
> This patch uses the earlier Rules tweak to separate the benchmark
> results for fast and slow paths of exp and pow since those results
> don't make sense together.  The patch also adjusts the number of
> iterations to make each benchmark last ~10 sec (give or take a couple
> of seconds) on my system.  Mileage may vary on other systems, but the
> idea is to make the number of iterations high enough and roughly
> comparable.
> 
> Here's an example benchmark output on my Fedora 17 on core i7:
> 
> exp: ITERS:5e+08: TOTAL:11.6213s, MAX:102.573ns, MIN:16.316ns, 4.30245e+07 iter/s
> pow: ITERS:2e+08: TOTAL:12.1205s, MAX:187.642ns, MIN:58.18ns, 1.65009e+07 iter/s
> slowexp: ITERS:5e+06: TOTAL:8.81398s, MAX:3189.31ns, MIN:1726.46ns, 567281 iter/s
> slowpow: ITERS:100000: TOTAL:8.48876s, MAX:88725.7ns, MIN:83907.3ns, 11780.3 iter/s
> 
> Siddhesh
> 
> 	* benchtests/Makefile: Add benchmarks for slowpow and slowexp.
> 	(bench): Add slowexp and slowpow.
> 	(exp-ITER): Increase iterations.
> 	(pow-ITER): Likewise.
> 	* benchtests/exp-inputs: Change input.
> 	* benchtests/pow-inputs: Likewise.
> 	* benchtests/slowexp-inputs: New file.
> 	* benchtests/slowexp.c: New file.
> 	* benchtests/slowpow-inputs: New file.
> 	* benchtests/slowpow.c: New file.
> 
> diff --git a/benchtests/Makefile b/benchtests/Makefile
> index 74938b9..f301ed1 100644
> --- a/benchtests/Makefile
> +++ b/benchtests/Makefile
> @@ -43,17 +43,33 @@
>  #   See pow-inputs for an example.
>  
>  subdir := benchtests
> -bench := exp pow
> +bench := exp pow slowexp slowpow
>  
> -exp-ITER = 100000
> +# exp function fast path
> +exp-ITER = 5e8
>  exp-ARGLIST = double
>  exp-RET = double
>  LDFLAGS-bench-exp = -lm
>  
> -pow-ITER = 100000
> +# pow function fast path
> +pow-ITER = 2e8
>  pow-ARGLIST = double:double
>  pow-RET = double
>  LDFLAGS-bench-pow = -lm
>  
> +# exp function slowest path
> +slowexp-ITER = 5e6
> +slowexp-ARGLIST = double
> +slowexp-RET = double
> +slowexp-INCLUDE = slowexp.c
> +LDFLAGS-bench-slowexp = -lm
> +
> +# pow function slowest path
> +slowpow-ITER = 1e5
> +slowpow-ARGLIST = double:double
> +slowpow-RET = double
> +slowpow-INCLUDE = slowpow.c
> +LDFLAGS-bench-slowpow = -lm
> +
>  include ../Makeconfig
>  include ../Rules
> diff --git a/benchtests/exp-inputs b/benchtests/exp-inputs
> index a2086ba..d81cc07 100644
> --- a/benchtests/exp-inputs
> +++ b/benchtests/exp-inputs
> @@ -1 +1 @@
> -708.00096423260981737257679924368858
> +42
> diff --git a/benchtests/pow-inputs b/benchtests/pow-inputs
> index dbb1270..2f7cc03 100644
> --- a/benchtests/pow-inputs
> +++ b/benchtests/pow-inputs
> @@ -1 +1 @@
> -1.0000000000000020, 1.5
> +42.0, 42.0
> diff --git a/benchtests/slowexp-inputs b/benchtests/slowexp-inputs
> new file mode 100644
> index 0000000..a2086ba
> --- /dev/null
> +++ b/benchtests/slowexp-inputs
> @@ -0,0 +1 @@
> +708.00096423260981737257679924368858
> diff --git a/benchtests/slowexp.c b/benchtests/slowexp.c
> new file mode 100644
> index 0000000..92ac5e9
> --- /dev/null
> +++ b/benchtests/slowexp.c
> @@ -0,0 +1,19 @@
> +/* Define slowexp.
> +   Copyright (C) 2013 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library; if not, see
> +   <http://www.gnu.org/licenses/>.  */
> +
> +#define slowexp exp
> diff --git a/benchtests/slowpow-inputs b/benchtests/slowpow-inputs
> new file mode 100644
> index 0000000..dbb1270
> --- /dev/null
> +++ b/benchtests/slowpow-inputs
> @@ -0,0 +1 @@
> +1.0000000000000020, 1.5
> diff --git a/benchtests/slowpow.c b/benchtests/slowpow.c
> new file mode 100644
> index 0000000..08f436d
> --- /dev/null
> +++ b/benchtests/slowpow.c
> @@ -0,0 +1,19 @@
> +/* Define slowpow.
> +   Copyright (C) 2013 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library; if not, see
> +   <http://www.gnu.org/licenses/>.  */
> +
> +#define slowpow pow