Have the incremental upgrade process use less RAM

Feature Branch: feature/11131-endless-upgrade

Attachments

• 2017Q3.stats
• 2018Q1.stats
• 2017Q4.stats
• 2018Q2.stats
• 2018Q3.stats

Parent Task: #15283

Subtasks

• #17152

Related issues

• Related to #6877 (closed)
• Related to #10115 (closed)
• Related to #9373
• Related to #8415
• Related to #15955 (closed)
• Related to #16015 (closed)
• Related to #5502
• Blocks #16209

Original created by @intrigeri on 6876 (Redmine)