[gmx-developers] Wallcycle bug?

[Berk Hess]

Hi,

We didn't realize that modern x86 cpus no longer synchronize clocks 
between cores. We should get the fix for this merged asap:
https://gerrit.gromacs.org/#/c/5091/

Cheers,

Berk

On 09/15/2015 05:06 PM, David van der Spoel wrote:
> Hi,
>
> my patch stumbled over this issue in Jenkins:
>
> Program:     gmx mdrun, VERSION 5.2-dev-20150915-ef00eb4-local
> Source file: src/gromacs/timing/wallcycle.cpp (line 398)
> Function:    void subtract_cycles(wallcc_t *, int, int)
>
> Assertion failed:
> Condition: wcc[ewc_main].c >= wcc[ewc_sub].c
> Subcounter cannot have more ticks than parent
>
> For more information and tips for troubleshooting, please check the 
> GROMACS
> website at http://www.gromacs.org/Documentation/Errors
>
> Any clue? Or is this assertion just overly pedantic?