Comes with a few changes:
- Change the signature of some functions to accept groupid
- InsertShardPlacementRow
- DeleteShardPlacementRow
- UpdateShardPlacementState
- NodeHasActiveShardPlacements returns true if the group the node is a
part of has any active shard placements
- TupleToShardPlacement now returns ShardPlacements which have NULL
nodeName and nodePort.
- Populate (nodeName, nodePort) when creating ShardPlacements
- Disallow removing a node if it contains any shard placements
- DeleteAllReferenceTablePlacementsFromNode matches based on group. This
doesn't change behavior for now (while there is only one node per
group), but means in the future callers should be careful about
calling it on a secondary node, it'll delete placements on the primary.
- Create concept of a GroupShardPlacement, which represents an actual
tuple in pg_dist_placement and is distinct from a ShardPlacement,
which has been resolved to a specific node. In the future
ShardPlacement should be renamed to NodeShardPlacement.
- Create some triggers which allow existing code to continue to insert
into and update pg_dist_shard_placement as if it still existed.
These functions are holdovers from pg_shard and were created for unit
testing c-level functions (like InsertShardPlacementRow) which our
regression tests already test quite effectively. Removing because it
makes refactoring the signatures of those c-level functions
unnecessarily difficult.
- create_healthy_local_shard_placement_row
- update_shard_placement_row_state
- delete_shard_placement_row
Uncrustify 0.65 appears to have changed some defaults, resulting in
breakages for those of us who have already upgraded; Travis still uses
Uncrustify 0.64, but these changes work with both versions (assuming
appropriately updated config), so this should permit use of either
version for the time being.
Before this change, we used ShareLock to acquire lock on distributed tables while
running VACUUM. This makes VACUUM and INSERT block each other. With this change we
changed lock mode from ShareLock to ShareUpdateExclusiveLock, which does not conflict
with the locks INSERT acquire.
MasterIrreducibleExpressionWalker has a copied code from
function check_functions_in_node() which was available with
PG 9.6+. Now PG 9.5 support is dropped we can remove
duplicate code and directly call check_functions_in_node().
Previously we used ForgetResults() in StartRemoteTransactionAbort() -
that's problematic because there might still be an ongoing statement,
and this causes us to wait for its completion. That e.g. happens when
a statement running on the coordinator is cancelled.
That's important because the currently running statement on a worker
might continue to hold locks and consume resources, even after the
connection is closed. Unfortunately postgres will only notice closed
connections when reading from / writing to the network. That might
only happen much later.
Now that there's no blocking libpq callers left, default to using
non-blocking mode in connection_management.c. This has two
advantages:
1) Blockiness doesn't have to frequently be reset, simplifying code
2) Prevents accidental use of blocking libpq functions, since they'll
frequently return 'need IO'
Marco Slot
Önder Kalacı
Burak Yucesoy
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Brian Cloutier
Jason Petersen
Murat Tuncer
Andres Freund
Burak Velioglu