Geodesic
Optimization of the Gyroaverage operator based on Hermite interpolation
Fabien Rozar1, 2 ; Christophe Steiner3 ; Guillaume Latu2 ; Michel Mehrenberger3 ; Virginie Grandgirard2 ; Julien Bigot1 ; Thomas Cartier-Michaud2 ; Jean Roman4
1Maison de la Simulation, USR 3441, CEA / CNRS / Inria / Univ. Paris-Sud / Univ. Versailles, 91191 Gif-sur-Yvette, FRANCE
2CEA, IRFM, F-13108 Saint-Paul-lez-Durance
3IRMA, Université de Strasbourg, France
4Inria, Bordeaux INP, CNRS, FR-33405 Talence
ESAIM. Proceedings, Tome 53 (2016), pp. 191-210
Cet article a éte moissonné depuis la source EDP Sciences

Voir la notice de l'article

Gyrokinetic modeling is appropriate for describing Tokamak plasma turbulence, and the gyroaverage operator is a cornerstone of this approach. In a gyrokinetic code, the gyroaveraging scheme needs to be accurate enough to avoid spoiling the data but also requires a low computation cost because it is applied often on the main unknown, the 5D guiding-center distribution function, and on the 3D electric potentials. In the present paper, we improve a gyroaverage scheme based on Hermite interpolation used in the Gysela code. This initial implementation represents a too large fraction of the total execution time. The gyroaverage operator has been reformulated and is now expressed as a matrix-vector product and a cache-friendly algorithm has been setup. Different techniques have been investigated to quicken the computations by more than a factor two. Description of the algorithms is given, together with an analysis of the achieved performance.
DOI : 10.1051/proc/201653012

Fabien Rozar  1 , 2   ; Christophe Steiner  3   ; Guillaume Latu  2   ; Michel Mehrenberger  3   ; Virginie Grandgirard  2   ; Julien Bigot  1   ; Thomas Cartier-Michaud  2   ; Jean Roman  4

1 Maison de la Simulation, USR 3441, CEA / CNRS / Inria / Univ. Paris-Sud / Univ. Versailles, 91191 Gif-sur-Yvette, FRANCE
2 CEA, IRFM, F-13108 Saint-Paul-lez-Durance
3 IRMA, Université de Strasbourg, France
4 Inria, Bordeaux INP, CNRS, FR-33405 Talence 
@article{EP_2016_53_a12,
     author = {Fabien Rozar and Christophe Steiner and Guillaume Latu and Michel Mehrenberger and Virginie Grandgirard and Julien Bigot and Thomas Cartier-Michaud and Jean Roman},
     title = {Optimization of the {Gyroaverage} operator based on {Hermite} interpolation},
     journal = {ESAIM. Proceedings},
     pages = {191--210},
     year = {2016},
     volume = {53},
     doi = {10.1051/proc/201653012},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.1051/proc/201653012/}
}
TY  - JOUR
AU  - Fabien Rozar
AU  - Christophe Steiner
AU  - Guillaume Latu
AU  - Michel Mehrenberger
AU  - Virginie Grandgirard
AU  - Julien Bigot
AU  - Thomas Cartier-Michaud
AU  - Jean Roman
TI  - Optimization of the Gyroaverage operator based on Hermite interpolation
JO  - ESAIM. Proceedings
PY  - 2016
SP  - 191
EP  - 210
VL  - 53
UR  - http://geodesic.mathdoc.fr/articles/10.1051/proc/201653012/
DO  - 10.1051/proc/201653012
LA  - en
ID  - EP_2016_53_a12
ER  - 
%0 Journal Article
%A Fabien Rozar
%A Christophe Steiner
%A Guillaume Latu
%A Michel Mehrenberger
%A Virginie Grandgirard
%A Julien Bigot
%A Thomas Cartier-Michaud
%A Jean Roman
%T Optimization of the Gyroaverage operator based on Hermite interpolation
%J ESAIM. Proceedings
%D 2016
%P 191-210
%V 53
%U http://geodesic.mathdoc.fr/articles/10.1051/proc/201653012/
%R 10.1051/proc/201653012
%G en
%F EP_2016_53_a12
Fabien Rozar; Christophe Steiner; Guillaume Latu; Michel Mehrenberger; Virginie Grandgirard; Julien Bigot; Thomas Cartier-Michaud; Jean Roman. Optimization of the Gyroaverage operator based on Hermite interpolation. ESAIM. Proceedings, Tome 53 (2016), pp. 191-210. doi: 10.1051/proc/201653012

Cité par Sources :