e6fe9cc683
Reapply: "disable_auto_compaction: stop ongoing compactions" This is a reapplication of a former commit4affa801a5which was reverted by8e8dc2c930. This commit is a fixed version of the original where a call to the compaction_manager constructor accidentally issued (`compaction_manager()`) instead a call to retrieve a compaction manager reference (`get_compaction_manager()`), we don't use this function because it doesn't exist anymore - it existed at the time the patch was written bu was removed in9066224cf4later on, instead, we just use the private table member _compaction_manager which refs the compaction manager. The explanation for the bad effect is probably that a `this` pointer capture down the call chain, resulted in a use after free which had an unknown effect on the system. (memory corruption at startup). Test: unit (dev,debug) write performance test as the one used to find the bug. A screenshot of the performance test can be found at https://github.com/scylladb/scylla/issues/10146/#issuecomment-1129578381 Fixes https://github.com/scylladb/scylla/issues/9313 Refs https://github.com/scylladb/scylla/issues/10146 For completeness, the original commit message was: The api call disables new regular compaction jobs from starting but it doesn't wait for ongoing compaction to stop and so it's much less useful. Returning after stopping regular compaction jobs and waiting for them to stop guarantees that no regular compactions job are running when nodetool disableautocompaction returns successfully. Signed-off-by: Eliran Sinvani <eliransin@scylladb.com> Closes #10597 * github.com:scylladb/scylla: compaction_manager: Make invoking the empty constructor more explicit Reapply: "disable_auto_compaction: stop ongoing compactions"
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.