b4fc3578fc
This PR enables **LWT (Lightweight Transactions)** support for tablet-based tables by leveraging **colocated tables**.
Currently, storing Paxos state in system tables causes two major issues:
* **Loss of Paxos state during tablet migration or base table rebuilds**
* When a tablet is migrated or the base table is rebuilt, system tables don't retain Paxos state.
* This breaks LWT correctness in certain scenarios.
* Failing test cases demonstrating this:
* test_lwt_state_is_preserved_on_tablet_migration
* test_lwt_state_is_preserved_on_rebuild
* **Shard misalignment and performance overhead**
* Tablets may be placed on arbitrary shards by the tablet balancer.
* Accessing Paxos state in system tables could require a shard jump, degrading performance.
We move Paxos state into a dedicated Paxos table, colocated with the base table:
* Each base table gets its own Paxos state table.
* This table is lazily created on the first LWT operation.
* Its tablets are colocated with those of the base table, ensuring:
* Co-migration during tablet movement
* Co-rebuilding with the base table
* Shard alignment for local access to Paxos state
Some reasoning for why this is sufficient to preserve LWT correctness is discussed in [2].
This PR addresses two issues from the "Why doesn't it work for tablets" section in [1]:
* Tablet migration vs LWT correctness
* Paxos table sharding
Other issues ("bounce to shard" and "locking for intranode_migration") have already been resolved in previous PRs.
References
[1] - [LWT over tablets design](https://docs.google.com/document/d/1CPm0N9XFUcZ8zILpTkfP5O4EtlwGsXg_TU4-1m7dTuM/edit?tab=t.0#heading=h.goufx7gx24yu)
[2] - [LWT: Paxos state and tablet balancer](https://docs.google.com/document/d/1-xubDo612GGgguc0khCj5ukmMGgLGCLWLIeG6GtHTY4/edit?tab=t.0)
[3] - [Colocated tables PR](https://github.com/scylladb/scylladb/pull/22906#issuecomment-3027123886)
[4] - [Possible LWT consistency violations after a topology change](https://github.com/scylladb/scylladb/issues/5251)
Backport: not needed because this is a new feature.
Closes scylladb/scylladb#24819
* github.com:scylladb/scylladb:
create_keyspace: fix warning for tablets
docs: fix lwt.rst
docs: fix tablets.rst
alternator: enable LWT
random_failures: enable execute_lwt_transaction
test_tablets_lwt: add test_paxos_state_table_permissions
test_tablets_lwt: add test_lwt_for_tablets_is_not_supported_without_raft
test_tablets_lwt: test timeout creating paxos state table
test_tablets_lwt: add test_lwt_concurrent_base_table_recreation
test_tablets_lwt: add test_lwt_state_is_preserved_on_rebuild
test_tablets_lwt: migrate test_lwt_support_with_tablets
test_tablets_lwt: add test_lwt_state_is_preserved_on_tablet_migration
test_tablets_lwt: add simple test for LWT
check_internal_table_permissions: handle Paxos state tables
client_state: extract check_internal_table_permissions
paxos_store: handle base table removal
database: get_base_table_for_tablet_colocation: handle paxos state table
paxos_state: use node_local_only mode to access paxos state
query_options: add node_local_only mode
storage_proxy: handle node_local_only in query
storage_proxy: handle node_local_only in mutate
storage_proxy: introduce node_local_only flag
abstract_replication_strategy: remove unused using
storage_proxy: add coordinator_mutate_options
storage_proxy: rename create_write_response_handler -> make_write_response_handler
storage_proxy: simplify mutate_prepare
paxos_state: lazily create paxos state table
migration_manager: add timeout to start_group0_operation and announce
paxos_store: use non-internal queries
qp: make make_internal_options public
paxos_store: conditional cf_id filter
paxos_store: coroutinize
feature_service: add LWT_WITH_TABLETS feature
paxos_state: inline system_keyspace functions into paxos_store
paxos_state: extract state access functions into paxos_store
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