Changes

• Reduced memory footprint for large putative phase blocks by adjusting algorithms for storing read segment variants. Overall, this change has a negligible impact on memory usage for a typical human WGS dataset. However, sample types with much higher heterozygous variants per phase block (e.g., mouse) have significantly less peak memory usage (>80% reduction on tests).
• Minor tweaks to phasing methods to reduce overhead of tracking candidate phase solutions
• Internal results are highly similar, but not identical, to results for v1.4.5