Milc with Scidac c carleton DeTar

MILC with SciDAC C

• Carleton DeTar

• HackLatt 2008

SciDAC Software Team

SciDAC/C Tutorial 2007

• James Osborn and Andrew Pochinski

• http://web.mit.edu/~bgl/scidac-2007/

New: Installation qinstall

• CVSROOT = :pserver:[e-mail]:/group/lattice/cvsroot

• cvs -d $CVSROOT co -P qinstall

• Profile for each processor type

Level 1

• QMP (message passing)

• MPI
• QCDOC

• QLA (single-processor linear algebra)

• Some 25,000 Perl-generated routines
• in a couple dozen libraries

Level 2

• QIO (file I/O)

• USQCD file formats
• ILDG file formats
• Create your own format
• LIME (message encapsulation – tar-like)

• QDP (data parallel operations)

Example of QDP coding

• Plaquette calculation

QDP/C vs QDP++

• Procedure calls straightfoward but cumbersome

• Optimization inherited from QLA

• Proliferation of precompiled procedures

Level 3

• QOP (inverters, Dslash, fermion force)

• QCDOC implementation
• QDP implementation

• Can be implemented in assembly

MILC Makefile Options for SciDAC

Summary

• SciDAC/C is supported by the MILC code

• Makefile options select the desired level of integration with SciDAC/C

Tutorial 2 goals

• Build MILC code with SciDAC support

• Create a gauge file in SciDAC format

• Learn how to use qinstall