[FLINK-14936] Introduce MemoryManager#computeMemorySize to calculate managed memory from a fraction

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Done
• Affects Version/s: 1.10.0
• Fix Version/s: 1.10.0
• Component/s: Runtime / Coordination
• Labels: pull-request-available
• Assignee: Zhu Zhu
• Reporter: Zhu Zhu
• Created: 25/Nov/19 07:00
• Updated: 03/Dec/19 16:06
• Resolved: 03/Dec/19 16:06

Description

A MemoryManager#computeMemorySize(double fraction) is needed to calculate managed memory bytes from a fraction.
It can be helpful for operators to get the memory size it can reserve and for further #reserveMemory. (Similar to #computeNumberOfPages).

Here are two cases that may need this method in near future:
1. Python operator memory management
2. Statebackend memory management

Issue Links

• is related to: FLINK-15037 Introduce LimittingMemoryManager as operator scope MemoyManager
• links to: GitHub Pull Request #10398