Running Search Mode

Running Search Mode

search mode is designed for efficient structure search and low-energy configuration discovery.

Concept

Search mode uses two worker classes:

• fast workers perform coarse screening relaxations
• slow workers perform accurate refinement relaxations

The C++ master keeps fast-worker slots full and slow workers consume candidates from waiting_pool.

Basic Search Command

paipai \
  --input struc.in \
  --mode search \
  --device cuda \
  --ngpu 4 \
  --fast 2 \
  --slow 2 \
  --steps 200000 \
  --temp 50 \
  --fmax-screen 0.1 \
  --max-steps-screen 100 \
  --fmax-refine 0.01 \
  --max-steps-refine 500

Move Weights

Example:

--p-swap-metal 60 \
--p-swap-inter 10 \
--p-cluster-inter 30 \
--p-hop-inter 0

The move probabilities are proportional to the supplied nonnegative weights. For search/prefast runs, use --p-hop-inter 0 unless deliberately testing local-hop proposals.

Search Mode and Interstitial Relaxation

In search mode, relaxed interstitial atoms may move to nearby candidate sites during relaxation. PAIPAI can reassign them to valid reference sites and rewrite the accepted SAVE.

The assignment cutoff is controlled by:

--interstitial-site-cutoff 1.5

Search with Prefast

On v2.1-dev:

--prefast on \
--prefast-warmup-steps 1000 \
--prefast-candidates-per-slot 6 \
--prefast-diagnostics summary

Prefast first learns from warmup proposals without multi-candidate ranking, then ranks multiple trial proposals before fast-worker screening. See Prefast Mode.