5f55787e50
initial implementation to support CDC in tablets-enabled keyspaces. The design is described in https://docs.google.com/document/d/1qO5f2q5QoN5z1-rYOQFu6tqVLD3Ha6pphXKEqbtSNiU/edit?usp=sharing It is followed closely for the most part except "Deciding when to change streams" - instead, streams are changed synchronously with tablet split / merge. Instead of the stream switching algorithm with the double writes, we use a scheme similar to the previous method for vnodes - we add the new streams with timestamp that is sufficiently far into the future. In this PR we: * add new group0-based internal system tables for tablet stream metadata and loading it into in-memory CDC metadata * add virtual tables for CDC consumers * the write coordinator chooses a stream by looking up the appropriate stream in the CDC metadata * enable creating tables with CDC enabled in tablets-enabled keyspaces. tablets are allocated for the CDC table, and a stream is created per each tablet. * on tablet resize (split / merge), the topology coordinator creates a new stream set with a new stream for each new tablet. * the cdc tablets are co-located with the base tablets Fixes https://github.com/scylladb/scylladb/issues/22576 backport not needed - new feature update dtests: https://github.com/scylladb/scylla-dtest/pull/5897 update java cdc library: https://github.com/scylladb/scylla-cdc-java/pull/102 update rust cdc library: https://github.com/scylladb/scylla-cdc-rust/pull/136 Closes scylladb/scylladb#23795 * github.com:scylladb/scylladb: docs/dev: update CDC dev docs for tablets doc: update CDC docs for tablets test: cluster_events: enable add_cdc and drop_cdc test/cql: enable cql cdc tests to run with tablets test: test_cdc_with_alter: adjust for cdc with tablets test/cqlpy: adjust cdc tests for tablets test/cluster/test_cdc_with_tablets: introduce cdc with tablets tests cdc: enable cdc with tablets topology coordinator: change streams on tablet split/merge cdc: virtual tables for cdc with tablets cdc: generate_stream_diff helper function cdc: choose stream in tablets enabled keyspaces cdc: rename get_stream to get_vnode_stream cdc: load tablet streams metadata from tables cdc: helper functions for reading metadata from tables cdc: colocate cdc table with base cdc: remove streams when dropping CDC table cdc: create streams when allocating tablets migration_listener: add on_before_allocate_tablet_map notification cdc: notify when creating or dropping cdc table cdc: move cdc table creation to pre_create cdc: add internal tables for cdc with tablets cdc: add cdc_with_tablets feature flag cdc: add is_log_schema helper
Scylla developer documentation
This folder contains developer-oriented documentation concerning the ScyllaDB codebase. We also have a wiki, which contains additional developer-oriented documentation. There is currently no clear definition of what goes where, so when looking for something be sure to check both.
Seastar documentation can be found here.
User documentation can be found on docs.scylladb.com
For information on how to build Scylla and how to contribute visit HACKING.md and CONTRIBUTING.md.