62a4d2d92b
What's contained in this series:
- Refactored compaction tests (and utilities) for integration with multiple groups
- The idea is to write a new class of tests that will stress multiple groups, whereas the existing ones will still stress a single group.
- Fixed a problem when cloning compound sstable set (cannot be triggered today so I didn't open a GH issue)
- Many changes in replica::table for allowing integration with multiple groups
Next:
- Introduce for_each_compaction_group() for iterating over groups wherever needed.
- Use for_each_compaction_group() in replica::table operations spanning all groups (API, readers, etc).
- Decouple backlog tracker from compaction strategy, to allow for backlog isolation across groups
- Introduce static option for defining number of compaction groups and implement function to map a token to its respective group.
- Testing infrastructure for multiple compaction groups (helpful when testing the dynamic behavior: i.e. merging / splitting).
Closes #11592
* github.com:scylladb/scylladb:
sstable_resharding_test: Switch to table_for_tests
replica: Move compacted_undeleted_sstables into compaction group
replica: Use correct compaction_group in try_flush_memtable_to_sstable()
replica: Make move_sstables_from_staging() robust and compaction group friendly
test: Rename column_family_for_tests to table_for_tests
sstable_compaction_test: Use column_family_for_tests::as_table_state() instead
test: Don't expose compound set in column_family_for_tests
test: Implement column_family_for_tests::table_state::is_auto_compaction_disabled_by_user()
sstable_compaction_test: Merge table_state_for_test into column_family_for_tests
sstable_compaction_test: use table_state_for_test itself in fully_expired_sstables()
sstable_compaction_test: Switch to table_state in compact_sstables()
sstable_compaction_test: Reduce boilerplate by switching to column_family_for_tests
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++20 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 APIs - CQL and Thrift. 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 users mailing list and Slack channel are for users to discuss configuration, management, and operations of the ScyllaDB open source.
- The developers mailing list is for developers and people interested in following the development of ScyllaDB to discuss technical topics.