Release date: 2023-07-10
PostgreSQL core and extensions:
Support for limit clause pushdown.
New external consistency mode for transactions:
Requires a known maximum gap between clocks in the cluster
Helps to avoid the stale read anomaly if an application performs write operation and then instantly accesses the data via a different node that has falling behind clocks
Enhancement of global sequence support:
Support for operations from an unprivileged user
Public.nextval can be used to acquire the next value instead of a custom function
Several bug fixes and performance optimization
Generic performance optimizations for queries with and without a sharding key.
Reduced memory consumption for a Silk worker and backend processes.
Silk worker processes are visible in pg_stat_activity.
Fixed deadlock detector: added some uncovered cases of distributed deadlocks.
Fixed resolution of prepared transactions:
In case of a broken service connection that is used to acquire the status of the transaction from a coordinator
In case of coordinator restart: the xid of the transaction could be reused and the status could be returned for a new wrong transaction
Various bug fixes including the fix for freezes in multiplexing transport (Silk) in some cases.
Management utilities:
Stolon services are integrated in shardmand:
Reduced number of administrated processes
Root privileges and interaction with dbus/systemd are not required to start services.
Implementation of demote for a master node that has problems with a network connection to etcd:
Helps to avoid stale read anomaly in fault-tolerance mode if read operations are performed from a stale master node
Optionally master can be configured in less strict mode to get status from its replica in addition to etcd
Added consistent fault-tolerance mode when a failed replica can be safely and automatically disconnected from a cluster.
Ability to show the current configuration with shardmanctl config get command.
Ability to add several replicas with shardmanctl shard add command.
Repfactor can be changed in manual topology mode.
Ability to configure trust method for local access, when in other cases a different method is used.
New status page for shardmand.
Manual rebalancing of partitions.
Enhancement of shardmanctl load:
Ability to rename tables for full schema migration procedure
Primary key is not required for sharded tables
New options in schema config: default number of partitions, exclusion list for tables, manual assignement of primary keys
Several bug fixes and performance optimization.