Re: [Boost-users] [spirit] benchmarks/qi benchmarks valid?

Subject: Re: [Boost-users] [spirit] benchmarks/qi benchmarks valid?
From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2009-09-14 10:28:48

AMDG

Daniel Mierswa wrote:
> I was merely wondering if what I'm doing is right or if I fail at 
> basic benchmarking:
>
> impulze_at_istari ~/dev/repositories/boost.svn/libs/spirit/benchmarks/qi 
> $ g++ -O3 int_parser.cpp -I../../../../ -lrt && ./a.out
> <snip>
> atoi_test:            5.0041852930 [s] {checksum: 13f6bf40}
> strtol_test:          5.4193627260 [s] {checksum: 13f6bf40}
> spirit_int_test:      2.2137115780 [s] {checksum: 13f6bf40}
>
>
> impulze_at_istari ~/dev/repositories/boost.svn/libs/spirit/benchmarks/qi 
> $ g++ -O0 int_parser.cpp -I../../../../ -lrt && ./a.out
> <snip>
> atoi_test:            0.5902040060 [s] {checksum: e9ed193a}
> strtol_test:          0.6001010490 [s] {checksum: e9ed193a}
> spirit_int_test:      3.6562933090 [s] {checksum: e9ed193a}

-O0 means no optimization.

> According to this, the optimized binary is 10 times slower wrt to the 
> atoi/strtol implementation. I find that somehow quite hard to believe, 
> is my toolchain broken, the testsuite or is it really true? The level 
> of optimization doesn't matter btw, I get similar results with -O[,1,2]

In Christ,
Steven Watanabe