mirror of
https://github.com/scylladb/scylladb.git
synced 2026-06-01 12:36:56 +00:00
3fce43124a
Allows static configuration of number of compaction groups per table per shard. To bootstrap the project, config option x_log2_compaction_groups was added which controls both number of groups and partitioning within a shard. With a value of 0 (default), it means 1 compaction group, therefore all tokens go there. With a value of 3, it means 8 compaction groups, and 3 most-significant-bits of tokens being used to decide which group owns the token. And so on. It's still missing: - integration with repair / streaming - integration with reshard / reshape. perf/perf_simple_query --smp 1 --memory 1G BEFORE ----- median 61358.55 tps ( 71.1 allocs/op, 12.2 tasks/op, 56375 insns/op, 0 errors) median 61322.80 tps ( 71.1 allocs/op, 12.2 tasks/op, 56391 insns/op, 0 errors) median 61058.58 tps ( 71.1 allocs/op, 12.2 tasks/op, 56386 insns/op, 0 errors) median 61040.94 tps ( 71.1 allocs/op, 12.2 tasks/op, 56381 insns/op, 0 errors) median 61118.40 tps ( 71.1 allocs/op, 12.2 tasks/op, 56379 insns/op, 0 errors) AFTER ----- median 61656.12 tps ( 71.1 allocs/op, 12.2 tasks/op, 56486 insns/op, 0 errors) median 61483.29 tps ( 71.1 allocs/op, 12.2 tasks/op, 56495 insns/op, 0 errors) median 61638.05 tps ( 71.1 allocs/op, 12.2 tasks/op, 56494 insns/op, 0 errors) median 61726.09 tps ( 71.1 allocs/op, 12.2 tasks/op, 56509 insns/op, 0 errors) median 61537.55 tps ( 71.1 allocs/op, 12.2 tasks/op, 56491 insns/op, 0 errors) Closes #12139 * github.com:scylladb/scylladb: test: mutation_test: Test multiple compaction groups test: database_test: Test multiple compaction groups test: database_test: Adapt it to compaction groups db: Add config for setting static number of compaction groups replica: Introduce static compaction groups test: sstable_test: Stop referencing single compaction group api: compaction_manager: Stop a compaction type for all groups api: Estimate pending tasks on all compaction groups api: storage_service: Run maintenance compactions on all compaction groups replica: table: Adapt assertion to compaction groups replica: database: stop and disable compaction on behalf of all groups replica: Introduce table::parallel_foreach_table_state() replica: disable auto compaction on behalf of all groups replica: table: Rework compaction triggers for compaction groups replica: Adapt table::get_sstables_including_compacted_undeleted() to compaction groups replica: Adapt table::rebuild_statistics() to compaction groups replica: table: Perform major compaction on behalf of all groups replica: table: Perform off-strategy compaction on behalf of all groups replica: table: Perform cleanup compaction on behalf of all groups replica: Extend table::discard_sstables() to operate on all compaction groups replica: table: Create compound sstable set for all groups replica: table: Set compaction strategy on behalf of all groups replica: table: Return min memtable timestamp across all groups replica: Adapt table::stop() to compaction groups replica: Adapt table::clear() to compaction groups replica: Adapt table::can_flush() to compaction groups replica: Adapt table::flush() to compaction groups replica: Introduce parallel_foreach_compaction_group() replica: Adapt table::set_schema() to compaction groups replica: Add memtables from all compaction groups for reads replica: Add memtable_count() method to compaction_group replica: table: Reserve reader list capacity through a callback replica: Extract addition of memtables to reader list into a new function replica: Adapt table::occupancy() to compaction groups replica: Adapt table::active_memtable() to compaction groups replica: Introduce table::compaction_groups() replica: Preparation for multiple compaction groups scylla-gdb: Fix backward compatibility of scylla_memtables command
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.