[SYSTEMDS-2160] Incorporate sparsity in lower bound costs

• Type: Sub-task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: SystemML 1.1
• Assignee: Matthias Boehm
• Reporter: Matthias Boehm
• Created: 23/Feb/18 00:26
• Updated: 24/Feb/18 09:35
• Resolved: 24/Feb/18 09:35

Description

So far, the codegen optimizer computes the lower bound costs for cost-based pruning without proper awareness of sparsity exploiting operators. This led to suboptimal plans because sub areas of the search space are pruned too eagerly.