cai.zhang ac8c5fcd5d
enhance: Remove pre-marking segments as L2 during clustering compaction (#36799)
issue: #36686 

This pr will remove pre-marking segments as L2 during clustering
compaction in version 2.5, and ensure compatibility with version 2.4.

The core of this change is to **ensure that the many-to-many lineage
derivation logic is correct, making sure that both the parent and child
cannot simultaneously exist in the target segment view.**

feature:
  - Clustering compaction no longer marks the input segments as L2.
- Add a new field `is_invisible` to `segmentInfo`, and mark segments
that have completed clustering but have not yet built indexes as
`is_invisible` to prevent them from being loaded prematurely."
- Do not mark the input segment as `Dropped` before the clustering
compaction is completed.
- After compaction fails, only the result segment needs to be marked as
Dropped.

compatibility:
- If the upgraded task has not failed, there are no compatibility
issues.
- If the status after the upgrade is `MetaSaved`, then skip the stats
task based on whether TmpSegments is empty.
  - If the failure occurs before `MetaSaved`:
- there are no ResultSegments, and InputSegments have not been marked as
dropped yet.
    - the level of input segments need to revert to LastLevel
  - If the failure occurs after `MetaSaved`:
- ResultSegments have already been generated, and InputSegments have
been marked as Dropped. At this point, simply make the ResultSegments
visible.
- the level of ResultSegments needs to be set to L1(in order to
participate in mixCompaction)

---------

Signed-off-by: Cai Zhang <cai.zhang@zilliz.com>
2024-10-23 17:15:28 +08:00
..
2023-09-21 09:45:27 +08:00
2023-09-21 09:45:27 +08:00
2023-09-26 17:15:27 +08:00
2021-11-16 15:41:11 +08:00

Data Coordinator

Data cooridnator(datacoord for short) is the component to organize DataNodes and segments allocations.

Dependency

  • KV store: a kv store has all the meta info datacoord needs to operate. (etcd)
  • Message stream: a message stream to communicate statistics information with data nodes. (Pulsar)
  • Root Coordinator: timestamp, id and meta source.
  • Data Node(s): could be an instance or a cluster, actual worker group handles data modification operations.