[RFC] Lock elision "test suite", first draft

[Ondřej Bílka]

On Wed, Aug 07, 2013 at 02:07:23PM +0200, Dominik Vogt wrote:
> Test results on z/Architecture (zEC12)
> --------------------------------------
> 
> Test Setup:
> 
>   An lpar with eight CPUs on a ZEC12.  8 GiB RAM.
> 
> Test execution:
> 
>   Each test case was run ten times in a loop using an unpatched
>   glibc-2.15 (Ubuntu standard) ("old glibc"), a new glibc-2.18
>   with elision disabled ("elision n/a"), and a new glibc-2.18
>   with elision enabled ("elision on").
snip
> ./ets-t3
> =========
> 
> old glibc:
> ----------
> pct_best  : 100.00...%
> pct_mindev: 4.57...%
> pct_maxdev: 5.43...%
> pct_stddev: 3.61...%
> 
> elision n/a:
> ------------
> pct_best  : 96.79...%
> pct_mindev: 9.82...%
> pct_maxdev: 9.42...%
> pct_stddev: 5.71...%
> 
> elision on:
> -----------
> pct_best 593.48...%
> pct_mindev: 5.73...%
> pct_maxdev: 4.09...%
> pct_stddev: 3.43...%
> 
Do you know why elision is 6 times slower on this test?