[ORC-464] [C++] Avoid computing zigzag values for DELTA and SHORT_REPEAT encoding

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Component/s: C++
• Assignee: Unassigned
• Reporter: Fang Zheng
• Created: 28/Jan/19 20:02
• Updated: 25/Feb/19 19:59

Description

In current implementation, RleEncoderV2::determineEncoding() always computes zigzag values before determining the encoding type. However, zigzag values are only needed for DIRECT and PATCHED_BASE encoding, but not for DELTA and SHORT_REPEAT. For efficiency
, we shall only perform zigzag computation when it's determined to be necessary.

Issue Links

• links to: GitHub Pull Request #361