high-performance multi-user code development with google code current status (...just google for...
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High-performance multi-user code High-performance multi-user code development with Google Codedevelopment with Google Code
Current status
(...just google for Pencil Code)
PencilPencilcodecode
• Started in Sept. 2001 with Wolfgang Dobler• High order (6th order in space, 3rd order in time)• Cache & memory efficient• MPI, can run PacxMPI (across countries!)• Maintained/developed by ~40 people (SVN)• Automatic validation (over night or any time)• 0.0013 s/pt/step at 10243 , 2048 procs• http://pencil-code.googlecode.com
• Isotropic turbulence– MHD, passive scl, CR
• Stratified layers– Convection, radiation
• Shearing box– MRI, dust, interstellar– Self-gravity
• Sphere embedded in box– Fully convective stars– geodynamo
• Other applications– Chemistry, combustion– Spherical coordinates
PencilPencilCodeCode
• Started in Sept. 2001 with Wolfgang Dobler• High order (6th order in space, 3rd order in time)• Cache & memory efficient• MPI, can run PacxMPI (across countries!)• Maintained/developed by ~40 people (SVN)• Automatic validation (over night or any time)• Max resolution so far 10243 , 4096 procs• http://pencil-code.googlecode.com
• Isotropic turbulence– MHD, passive scl, CR
• Stratified layers– Convection, radiation
• Shearing box– MRI, dust, interstellar– Self-gravity
• Sphere embedded in box– Fully convective stars– geodynamo
• Other applications– Homochirality– Spherical coordinates
8
Evolution of code sizeEvolution of code size
User meetings:User meetings:2005 Copenhagen2006 Copenhagen2007 Stockholm2008 Leiden2009 Heidelberg2010 New York2011 Toulouse2012 Helsinki
25
Hyperviscous, Smagorinsky, normalHyperviscous, Smagorinsky, normal
Inertial range unaffected by artificial diffusionHau
gen
& B
rand
enbu
rg (
PR
E, a
stro
-ph/
0402
301)
height of bottleneck increased
onset of bottleneck at same position
26
Online data reduction and visualizationOnline data reduction and visualization
non-helically forced turbulence
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MRI turbulenceMRI turbulenceMRI = magnetorotational instabilityMRI = magnetorotational instability
2563
w/o hypervisc.t = 600 = 20 orbits
5123
w/o hypervisc.t = 60 = 2 orbits
29
Vorticity and DensityVorticity and Density
See poster by Tobi Heinemann on density wave excitation!
30
Transfer equation & parTransfer equation & paraallelizationllelization
Analytic Solution:
Ray direction
Intrinsic Calculation
Processors
SII
d
d
31
The Transfer Equation & The Transfer Equation & ParParaallelizationllelization
Analytic Solution:
Ray direction
Communication
Processors
32
The Transfer Equation & The Transfer Equation & ParallelizationParallelization
Analytic Solution:
Ray direction
Processors
Intrinsic Calculation