[MESOS-9608] Refactor and Improve `class ResourceQuantity`.

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.8.0
• Labels: resource-management
• Epic Link: Quota Limits
• Sprint: Resource Mgmt RI11 Sp 40, Resource Mgmt RI11 Sp 41, Resource Mgmt RI12 Sp 42
• Story Points: 5
• Assignee: Meng Zhu
• Reporter: Meng Zhu
• Created: 25/Feb/19 22:05
• Updated: 18/Mar/19 21:05
• Resolved: 18/Mar/19 21:05

Description

Currently, the `ResourceQuantity` only provides a minimal map interface with no built-in arithmetic and contains operations. This makes it unwieldy.

The intention was to avoid the ambiguities between "absent-means-zero" (guarantee like semantic) and "absent-means-infinite" (limits like semantic). Instead of only providing a minimal interface and leave the rest to the caller, we should provide two classes for each semantic:

• "ResourceQuantities" will have "absent-means-zero" semantic
• "ResourceLimits" will have "absent-means-infinite" semantic