mirror of
https://github.com/scylladb/scylladb.git
synced 2026-05-12 19:02:12 +00:00
a8b9f94dcb
When multiple key columns (clustering or partition) are passed to
the schema constructor, all having the same column id, the expectation
is that these columns will retain the order in which they were passed to
`schema_builder::with_column()`. Currently however this is not
guaranteed as the schema constructor sort key columns by column id with
`std::sort()`, which doesn't guarantee that equally comparing elements
retain their order. This can be an issue for indexes, the schemas of
which are built independently on each node. If there is any room for
variance between for the key column order, this can result in different
nodes having incompatible schemas for the same index.
The fix is to use `std::stable_sort()` which guarantees that the order
of equally comparing elements won't change.
This is a suspected cause of #5856, although we don't have hard proof.
Fixes: #5856
Signed-off-by: Botond Dénes <bdenes@scylladb.com>
[avi: upgraded "Refs" to "Fixes", since we saw that std::sort() becomes
unstable at 17 elements, and the failing schema had a
clustering key with 23 elements]
Message-Id: <20200417121848.1456817-1-bdenes@scylladb.com>
(cherry picked from commit a4aa753f0f)
Scylla
Quick-start
To get the build going quickly, Scylla offers a frozen toolchain which would build and run Scylla using a pre-configured Docker image. Using the frozen toolchain will also isolate all of the installed dependencies in a Docker container. Assuming you have met the toolchain prerequisites, which is running Docker in user mode, building and running is as easy as:
$ ./tools/toolchain/dbuild ./configure.py
$ ./tools/toolchain/dbuild ninja build/release/scylla
$ ./tools/toolchain/dbuild ./build/release/scylla --developer-mode 1
Please see HACKING.md for detailed information on building and developing Scylla.
Note: GCC >= 8.1.1 is required to compile Scylla.
Running Scylla
- Run Scylla
./build/release/scylla
- run Scylla with one CPU and ./tmp as data directory
./build/release/scylla --datadir tmp --commitlog-directory tmp --smp 1
- For more run options:
./build/release/scylla --help
Scylla APIs and compatibility
By default, Scylla is compatible with Apache Cassandra and its APIs - CQL and Thrift. There is also experimental support for the API of Amazon DynamoDB, but being experimental it needs to be explicitly enabled to be used. For more information on how to enable the experimental DynamoDB compatibility in Scylla, and the current limitations of this feature, see Alternator and Getting started with Alternator.
Documentation
Documentation can be found in ./docs and on the wiki. 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 here.
Building Fedora RPM
As a pre-requisite, you need to install Mock on your machine:
# Install mock:
sudo yum install mock
# Add user to the "mock" group:
usermod -a -G mock $USER && newgrp mock
Then, to build an RPM, run:
./dist/redhat/build_rpm.sh
The built RPM is stored in /var/lib/mock/<configuration>/result directory.
For example, on Fedora 21 mock reports the following:
INFO: Done(scylla-server-0.00-1.fc21.src.rpm) Config(default) 20 minutes 7 seconds
INFO: Results and/or logs in: /var/lib/mock/fedora-21-x86_64/result
Building Fedora-based Docker image
Build a Docker image with:
cd dist/docker
docker build -t <image-name> .
Run the image with:
docker run -p $(hostname -i):9042:9042 -i -t <image name>