DESCRIPTION: Extend cleanup process for replication artifacts
This PR adds new cleanup record types for:
* Subscriptions
* Replication slots
* Publications
* Users created for subscriptions
We add records for these object types, to `pg_dist_cleanup` during
creation phase. Once the operation is done, in case of success or
failure, we iterate those records and drop the objects. With this PR we
will not be dropping any of these objects during the operation. In
short, we will always be deferring the drop.
One thing that's worth mentioning is that we sort cleanup records before
processing (dropping) them, because of dependency relations among those
objects, e.g a subscription might depend on a publication. Therefore, we
always drop subscriptions before publications.
We have some renames in this PR:
* `TryDropOrphanedShards` -> `TryDropOrphanedResources`
* `DropOrphanedShardsForCleanup` -> `DropOrphanedResourcesForCleanup`
* `run_try_drop_marked_shards` -> `run_try_drop_marked_resources`
as these functions now process replication artifacts as well.
This PR drops function `DropAllLogicalReplicationLeftovers` and its all
usages, since now we rely on the deferring drop mechanism.
DESCRIPTION: Drops GUC defer_drop_after_shard_split
DESCRIPTION: Drops GUC defer_drop_after_shard_move
Drop GUCs and related parts from the code.
Delete tests that specifically added for the GUCs.
Keep tests that can be used without the GUCs.
Update test output changes.
The motivation for this PR is to have an "always deferring" mechanism.
These two GUCs provide an option to not deferring dropping objects
during a shard move/split, and dropping them immediately. With this PR,
we will be always deferring dropping orphaned shards and other types of
objects.
We will have a separate PR to extend the deferred cleanup operation, so
that we would create records for deferred drop, for Subscriptions,
Publications, Replication Slots etc. This will make us be able to keep
track of created objects that needs to be dropped, during a shard
move/split. We will have objects created specifically for the current
operation; and those objects will be dropped at the end.
We have an issue (a draft roadmap) for enabling parallel shard moves.
For details please see: https://github.com/citusdata/citus/issues/6437
DESCRIPTION: Improve logging during shard split and resource cleanup
### DESCRIPTION
This PR makes logging improvements to Shard Split :
1. Update confusing logging to fix#6312
2. Added new `ereport(LOG` to make debugging easier as part of telemetry review.
DESCRIPTION:
This PR adds support for 'Deferred Drop' and robust 'Shard Cleanup' for Splits.
Common Infrastructure
This PR introduces new common infrastructure so as any operation that wants robust cleanup of resources can register with the cleaner and have the resources cleaned appropriately based on a specified policy. 'Shard Split' is the first consumer using this new infrastructure.
Note : We only support adding 'shards' as resources to be cleaned-up right now but the framework will be extended to support other resources in future.
Deferred Drop for Split
Deferred Drop Support ensures that shards undergoing split are not dropped inline as part of operation but dropped later when no active read queries are running on shard. This helps with :
Avoids any potential deadlock scenarios that can cause long running Split operation to rollback.
Avoids Split operation blocking writes and then getting blocked (due to running queries on the shard) when trying to drop shards.
Deferred drop is the new default behavior going forward.
Shard Cleaner Extension
Shard Cleaner is a background task responsible for deferred drops in case of 'Move' operations.
The cleaner has been extended to ensure robust cleanup of shards (dummy shards and split children) in case of a failure based on the new infrastructure mentioned above. The cleaner also handles deferred drop for 'Splits'.
TESTING:
New test ''citus_split_shard_by_split_points_deferred_drop' to test deferred drop support.
New test 'failure_split_cleanup' to test shard cleanup with failures in different stages.
Update 'isolation_blocking_shard_split and isolation_non_blocking_shard_split' for deferred drop.
Added non-deferred drop version of existing tests : 'citus_split_shard_no_deferred_drop' and 'citus_non_blocking_splits_no_deferred_drop'
Added create_distributed_table_concurrently which is nonblocking variant of create_distributed_table.
It bases on the split API which takes advantage of logical replication to support nonblocking split operations.
Co-authored-by: Marco Slot <marco.slot@gmail.com>
Co-authored-by: aykutbozkurt <aykut.bozkurt1995@gmail.com>
* Remove if conditions with PG_VERSION_NUM < 13
* Remove server_above_twelve(&eleven) checks from tests
* Fix tests
* Remove pg12 and pg11 alternative test output files
* Remove pg12 specific normalization rules
* Some more if conditions in the code
* Change RemoteCollationIdExpression and some pg12/pg13 comments
* Remove some more normalization rules
This PR makes all of the features open source that were previously only
available in Citus Enterprise.
Features that this adds:
1. Non blocking shard moves/shard rebalancer
(`citus.logical_replication_timeout`)
2. Propagation of CREATE/DROP/ALTER ROLE statements
3. Propagation of GRANT statements
4. Propagation of CLUSTER statements
5. Propagation of ALTER DATABASE ... OWNER TO ...
6. Optimization for COPY when loading JSON to avoid double parsing of
the JSON object (`citus.skip_jsonb_validation_in_copy`)
7. Support for row level security
8. Support for `pg_dist_authinfo`, which allows storing different
authentication options for different users, e.g. you can store
passwords or certificates here.
9. Support for `pg_dist_poolinfo`, which allows using connection poolers
in between coordinator and workers
10. Tracking distributed query execution times using
citus_stat_statements (`citus.stat_statements_max`,
`citus.stat_statements_purge_interval`,
`citus.stat_statements_track`). This is disabled by default.
11. Blocking tenant_isolation
12. Support for `sslkey` and `sslcert` in `citus.node_conninfo`
Ahmet Gedemenli
Marco Slot
Nitish Upreti
aykut-bozkurt
Marco Slot
Naisila Puka
Jelte Fennema