[Users] McLachlan help

[Erik Schnetter]

James

Also, what constraints are calculated by LazEv?

-erik

On Mon, Jul 27, 2015 at 4:56 PM, Erik Schnetter <schnetter at cct.lsu.edu>
wrote:

> Jim
>
> Thanks for posting the details.
>
> Can you give us more details about the LazEv scheme? In particular there
> may be differences in the gauge. What (gauge) variables do you evolve? What
> gauge conditions do you use? And what kind of dissipation do you apply? Can
> you point us to the source code?
>
> For the new McLachlan, you would probably use the built-in dissipation
> instead of thorn Dissipation, which should lead to a small speed-up.
>
> -erik
>
> On Mon, Jul 27, 2015 at 4:43 PM, James Healy <jchsma at rit.edu> wrote:
>
>> Hello,
>>
>> I have been running some tests on Stampede comparing the run speed of
>> McLachlan to RIT's evolution thorn LazEv.  I started with the
>> qc0-mclachlan.par parameter file included with the Einstein Toolkit, added
>> a few refinement levels, increased the resolution and changed McLachlan to
>> be 8th order (and increased the number of ghost zones to 5).  I also
>> increased the initial separation so the finest grids aren't already
>> overlapping.  To compare with LazEv, I removed the McLachlan and
>> Dissipation thorns and replaced them with LazEv. Everything else in the
>> parameter file is exactly the same.  I tried using both the McLachlan
>> master and rewrite branches.
>>
>> The grid setup is 10 levels of refinement, dx=4M on the coarsest with
>> outer boundary at 400M, M/128 on the finest with r=0.6M, CFL is 0.25.  Both
>> use 8th order spatial differencing with ghost_size=5 and 5th order
>> dissipation.
>>
>> Below is a summary of the results as reported at iteration 256 from
>> Carpet::physical_time_per_hour:
>>
>> McLachlan - rewrite branch: 3.0596110 M/hr
>> McLachlan - master branch: 3.8033607 M/hr
>> LazEv - 4.1941544 M/hr
>>
>> I am using the stampede-impi.cfg configuration file in simfactory.
>> "module list" returns:
>>
>>   1) TACC-paths   3) cluster-paths      5) xalt/0.4.6   7) TACC
>>   2) Linux        4) intel/13.0.2.146   6) cluster      8) impi/4.1.0.030
>>
>>
>> Attached is my parameter file.  I pasted the McLachlan parameters below.
>> Are there any optimizations that I can use for McLachlan? Are the
>> parameters I am using for it what would be used for production runs?
>>
>> ML_BSSN::harmonicN           = 1      # 1+log
>> ML_BSSN::harmonicF           = 2.0    # 1+log
>> ML_BSSN::ShiftGammaCoeff     = 0.75
>> ML_BSSN::BetaDriver          = 1.0
>> ML_BSSN::LapseAdvectionCoeff = 1.0
>> ML_BSSN::ShiftAdvectionCoeff = 1.0
>>
>> ML_BSSN::MinimumLapse        = 1.0e-8
>>
>> ML_BSSN::my_initial_boundary_condition = "extrapolate-gammas"
>> ML_BSSN::my_rhs_boundary_condition     = "NewRad"
>> Boundary::radpower                     = 2
>>
>> ML_BSSN::ML_log_confac_bound = "none"
>> ML_BSSN::ML_metric_bound     = "none"
>> ML_BSSN::ML_Gamma_bound      = "none"
>> ML_BSSN::ML_trace_curv_bound = "none"
>> ML_BSSN::ML_curv_bound       = "none"
>> ML_BSSN::ML_lapse_bound      = "none"
>> ML_BSSN::ML_dtlapse_bound    = "none"
>> ML_BSSN::ML_shift_bound      = "none"
>> ML_BSSN::ML_dtshift_bound    = "none"
>>
>> ML_BSSN::fdOrder = 8
>>
>> ActiveThorns = "Dissipation"
>>
>> Dissipation::order = 5
>> Dissipation::vars  = "
>>         ML_BSSN::ML_metric
>>         ML_BSSN::ML_trace_curv
>>         ML_BSSN::ML_curv
>>         ML_BSSN::ML_Gamma
>>         ML_BSSN::ML_lapse
>>         ML_BSSN::ML_shift
>>         ML_BSSN::ML_dtlapse
>>         ML_BSSN::ML_dtshift
>> "
>>
>> ActiveThorns = "ML_ADMConstraints"
>>
>>
>> Thanks,
>> Jim Healy
>>
>> _______________________________________________
>> Users mailing list
>> Users at einsteintoolkit.org
>> http://lists.einsteintoolkit.org/mailman/listinfo/users
>>
>>
>
>
> --
> Erik Schnetter <schnetter at cct.lsu.edu>
> http://www.perimeterinstitute.ca/personal/eschnetter/
>



-- 
Erik Schnetter <schnetter at cct.lsu.edu>
http://www.perimeterinstitute.ca/personal/eschnetter/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.einsteintoolkit.org/pipermail/users/attachments/20150727/fb763d2f/attachment.html