[IGNITE-18134] Introduce common auto adjust scheduler

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Labels: dzm-reviewed ignite-3 tech-debt
• Assignee: Unassigned
• Reporter: Alexander Lapin
• Created: 11/Nov/22 13:40
• Updated: 17/Oct/23 10:04

Description

Motivation

IGNITE-18121 introduced DATA_NODES_AUTO_ADJUST_SCALE_UP scheduler and IGNITE-18132 SCALE_DOWN one. Let's take a look at the last remaining auto adjust property - DATA_NODES_AUTO_ADJUST. The reason we have one is to eliminate excessive rebalance in case of users intention on having the same value for both scale_up and scale_down. As we saw in the example above, the events of adding and removing nodes fall into the corresponding frames with a dedicated timer each: one for expanding the topology (adding nodes), and another for narrowing it (removing nodes), which in turn leads to two rebalances - one per each frame. If the user however wants to put both types of events (adding and removing nodes) in one frame with only one dataNodes recalculation and one rebalance, he should use the DATA_NODES_AUTO_ADJUST property.

Definition of Done

DataNodes recalculation transitively triggered by both node appeared and disappeared events is delayed for dataNodesAutoAdjust value.
In case of new logical topology event, existing auto adjust timer should be re-scheduled.

Implementation Notes

Same as for IGNITE-18121 and IGNITE-18132.

Issue Links

• is a child of: IGNITE-17924 Core distributions zones functionality.
• is blocked by: IGNITE-18132 Introduce scale down scheduler