[SYSTEMDS-2054] Performance features sparse-sparse leftindexing

• Type: Task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: SystemML 1.1
• Assignee: Matthias Boehm
• Reporter: Matthias Boehm
• Created: 31/Dec/17 04:55
• Updated: 31/Dec/17 06:54
• Resolved: 31/Dec/17 06:54

Description

This task aims to improve the sparse-sparse left indexing performance, which includes:

• Shallow copy of sparse rows into empty target rows (0 aligned)
• Exact preallocation of sparse rows for coping rows into empty target rows (not 0 aligned)
• New set index range with input sparse row to avoid repeated binary search and shifting.