56cc7bbeec
Refs: SCYLLADB-193 Adds a "snapshot_table" topology operation and associated data structure/table columns to support dispatching a snapshot operation as a topo coordinator op. Logic is similar, and thus broken out and semi-shared with, truncation. Also adds optional tablet metadata to manifest, listing all tablets present in a given snapshot, as well as tablet sstable ownership, repair status, and token ranges. As per description in SCYLLADB-193, the alternative snapshot mechanism is in a separate namespace under 'tablets', which while dubious is the desired destination. The API is accessed via `nodetool cluster snapshot`, which more or less mirrors `nodetool snapshot`, but using topo op. TTL is added to message propagation as a separate patch here, since it is not (yet) used from API (or nodetool). Requires a syntax for both API and command line. Closes scylladb/scylladb#28525 * github.com:scylladb/scylladb: topology::snapshot: Add expiry (ttl) to RPC/topo op test_snapshot_with_tablets: Extend test to check manifest content table::manifest: Add tablet info to manifest.json test::test_snapshot_with_tablets: Add small test for topo coordinated snapshot scylla-nodetool: Add "cluster snapshot" command api::storage_service: Add tablets/snapshots command for cluster level snapshot db::snapshot-ctl: Add method to do snapshot using topo coordinator storage_proxy: Add snapshot_keyspace method topology_coordinator: Add handler for snapshot_tables storage_proxy: Add handler for SNAPSHOT_WITH_TABLETS messaging_service: Add SNAPSHOT_WITH_TABLETS verb feature_service: Add SNAPSHOT_AS_TOPOLOGY_OPERATION feature topology_mutation: Add setter for snapshot part of row system_keyspace::topology_requests_entry: Add snapshot info to table topology_state_machine: Add snapshot_tables operation topology_coordinator: Break out logic from handle_truncate_table storage_proxy: Break out logic from request_truncate_with_tablets test/object_store: Remove create_ks_and_cf() helper test/object_store: Replace create_ks_and_cf() usage with standard methods test/object_store: Shift indentation right for test cases
Scylla
What is Scylla?
Scylla is the real-time big data database that is API-compatible with Apache Cassandra and Amazon DynamoDB. Scylla embraces a shared-nothing approach that increases throughput and storage capacity to realize order-of-magnitude performance improvements and reduce hardware costs.
For more information, please see the ScyllaDB web site.
Build Prerequisites
Scylla is fairly fussy about its build environment, requiring very recent versions of the C++23 compiler and of many libraries to build. The document HACKING.md includes detailed information on building and developing Scylla, but to get Scylla building quickly on (almost) any build machine, Scylla offers a frozen toolchain. This is a pre-configured Docker image which includes recent versions of all the required compilers, libraries and build tools. Using the frozen toolchain allows you to avoid changing anything in your build machine to meet Scylla's requirements - you just need to meet the frozen toolchain's prerequisites (mostly, Docker or Podman being available).
Building Scylla
Building Scylla with the frozen toolchain dbuild is as easy as:
$ git submodule update --init --force --recursive
$ ./tools/toolchain/dbuild ./configure.py
$ ./tools/toolchain/dbuild ninja build/release/scylla
For further information, please see:
- Developer documentation for more information on building Scylla.
- Build documentation on how to build Scylla binaries, tests, and packages.
- Docker image build documentation for information on how to build Docker images.
Running Scylla
To start Scylla server, run:
$ ./tools/toolchain/dbuild ./build/release/scylla --workdir tmp --smp 1 --developer-mode 1
This will start a Scylla node with one CPU core allocated to it and data files stored in the tmp directory.
The --developer-mode is needed to disable the various checks Scylla performs at startup to ensure the machine is configured for maximum performance (not relevant on development workstations).
Please note that you need to run Scylla with dbuild if you built it with the frozen toolchain.
For more run options, run:
$ ./tools/toolchain/dbuild ./build/release/scylla --help
Testing
See test.py manual.
Scylla APIs and compatibility
By default, Scylla is compatible with Apache Cassandra and its API - CQL. There is also support for the API of Amazon DynamoDB™, which needs to be enabled and configured in order to be used. For more information on how to enable the DynamoDB™ API in Scylla, and the current compatibility of this feature as well as Scylla-specific extensions, see Alternator and Getting started with Alternator.
Documentation
Documentation can be found here. Seastar documentation can be found here. User documentation can be found here.
Training
Training material and online courses can be found at Scylla University. The courses are free, self-paced and include hands-on examples. They cover a variety of topics including Scylla data modeling, administration, architecture, basic NoSQL concepts, using drivers for application development, Scylla setup, failover, compactions, multi-datacenters and how Scylla integrates with third-party applications.
Contributing to Scylla
If you want to report a bug or submit a pull request or a patch, please read the contribution guidelines.
If you are a developer working on Scylla, please read the developer guidelines.
Contact
- The community forum and Slack channel are for users to discuss configuration, management, and operations of ScyllaDB.
- The developers mailing list is for developers and people interested in following the development of ScyllaDB to discuss technical topics.