[GEODE-8624] Improve INCRBYFLOAT accuracy for very large values

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.14.0, 1.15.0
• Component/s: redis
• Labels: blocks-1.14.0​ pull-request-available
• Assignee: Unassigned
• Reporter: Jens Deppe
• Created: 16/Oct/20 18:52
• Updated: 03/Sep/21 02:26
• Resolved: 21/Oct/20 19:16

Description

Currently native redis appears to be able to apply INCRBYFLOAT on values that are below the max of unsigned long long (18446744073709551615). However, since we're treating numbers as {{double}}s we can lose precision for very large values. For example:

set val 18446744073709551614
incrbyfloat val 1

incorrectly returns 18446744073709552000

Native redis produces a correct result.

We should consider switching to using BigInteger for all commands which perform calculations: INCR, INCR, INCRBYFLOAT, HINCRBY, HINCRBYFLOAT.

Issue Links

• links to: GitHub Pull Request #5986