[SYSTEMDS-1269] Performance sparse matrix collect

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: SystemML 0.13
• Assignee: Matthias Boehm
• Reporter: Matthias Boehm
• Created: 15/Feb/17 06:41
• Updated: 15/Feb/17 18:57
• Resolved: 15/Feb/17 18:57

Description

In case of sparse matrices, our RDD collect functionality exhibits unnecessary overhead for (1) repeated sparse row allocations (due to missing exploitation of the number of non-zeros which affects the growth rate), and (2) deep copies of sparse rows (even in cases like a single column block, where this is not required).