DESCRIPTION: Drop `SHARD_STATE_TO_DELETE` and use the cleanup records
instead
Drops the shard state that is used to mark shards as orphaned. Now we
insert cleanup records into `pg_dist_cleanup` so "orphaned" shards will
be dropped either by maintenance daemon or internal cleanup calls. With
this PR, we make the "cleanup orphaned shards" functions to be no-op, as
they would not be needed anymore.
This PR includes some naming changes about placement functions. We don't
need functions that filter orphaned shards, as there will be no orphaned
shards anymore.
We will also be introducing a small script with this PR, for users with
orphaned shards. We'll basically delete the orphaned shard entries from
`pg_dist_placement` and insert cleanup records into `pg_dist_cleanup`
for each one of them, during Citus upgrade.
We also have a lot of flakiness fixes in this PR.
Co-authored-by: Jelte Fennema <github-tech@jeltef.nl>
DESCRIPTION: Defers cleanup after a failure in shard move or split
We don't need to do a cleanup in case of failure on a shard transfer or
split anymore. Because,
* Maintenance daemon will clean them up anyway.
* We trigger a cleanup at the beginning of shard transfers/splits.
* The cleanup on failure logic also can fail sometimes and instead of
the original error, we throw the error that is raised by the cleanup
procedure, and it causes confusion.
DESCRIPTION: Cleanup the shard on the target node in case of a
failed/aborted shard move
Inserts a cleanup record for the moved shard placement on the target
node. If the move operation succeeds, the record will be deleted. If
not, it will remain there to be cleaned up later.
fixes: #6580
When using multiline strings, we occasionally forget to add a single
space at the end of the first line. When this line is concatenated with
the next one, the resulting string has a missing space.
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
To be able to test non-blocking shard moves we take an advisory lock, so
we can pause the shard move at an interesting moment. Originally this
was during the logical replication catch up phase. But when I added
tests for the rebalancer progress I moved this lock before the initial
data copy. This allowed testing of the rebalance progress, but
inadvertently made our non-blocking tests not actually test if we held
unintended locks during logical replication catch up.
This fixes that by creating two types of advisory locks, one before the
copy and one after. This causes the tests to actually test their
intended scenario again.
Furthermore it starts using one of these locks for blocking shard moves
too. Which allowed me to reduce the complexity of the rebalance progress
test suite quite a bit. It also allowed enabling some flaky tests again,
because this stopped them from being flaky. And finally it allowed
testing of rebalance progress for blocking shard copy operations as
well.
In passing it fixes a flaky test during parallel blocking shard moves by
ordering the output.
DESCRIPTION: Adds status column to get_rebalance_progress()
Introduces a new column named `status` for the function
`get_rebalance_progress()`. For each ongoing shard move, this column
will reveal information about that shard move operation's current
status.
For now, candidate status messages could be one of the below.
* Not Started
* Setting Up
* Copying Data
* Catching Up
* Creating Constraints
* Final Catchup
* Creating Foreign Keys
* Completing
* Completed
DESCRIPTION: Show citus_copy_shard_placement progress in
get_rebalance_progress
When rebalancing to a new node that does not have reference tables yet
the rebalancer will first copy the reference tables to the nodes.
Depending on the size of the reference tables, this might take a long
time. However, there's no indication of what's happening at this stage
of the rebalance.
This PR improves this situation by also showing the progress of any
citus_copy_shard_placement calls when calling get_rebalance_progress.
Ahmet Gedemenli
Hanefi Onaldi
Marco Slot
Jelte Fennema
Jelte Fennema