Deflation

Deflation part in tmLQCD

bugs found / questions

• deflation does not work together with SSE 2/3 (28.8.2013)

• FIXED (20.9.2013) the scalar version (no MPI) does not work properly, it produces either a wrong little Dirac operator or the block boundaries are not treated correctly. With MPI different parallelisations but the same global block numbers give identical results, though.

  • little_D appears to be identical in between scalar and MPI version

• does it work for odd number of blocks in some or all directions per MPI task? More specifically, does the little GCR even/odd solver work properly then? --> only even no of blocks per MPI task and direction are allowed. This is checked for now explicitly in the code.

new features

• changed the preconditioning in FGMRES as suggested in arXiv:1303.1377
• included a deflated PCG solver with deflation subspace generation
• added a CG even/odd smoother
• included a deflated FGMRES solver for Qsq