ede1d248af
Currently, we use --sig-proxy to forward signals to the container. However, this
requires the container's co-operation, which usually doesn't exist. For example,
docker run --sig-proxy fedora:29 bash -c "sleep 5"
Does not respond to ctrl-C.
This is a problem for continuous integration. If a build is aborted, Jenkins will
first attempt to gracefully terminate the processes (SIGINT/SIGTERM) and then give
up and use SIGKILL. If the graceful termination doesn't work, we end up with an
orphan container running on the node, which can then consume enough memory and CPU
to harm the following jobs.
To fix this, trap signals and handle them by killing the container. Also trap
shell exit, and even kill the container unconditionally, since if Jenkins happens
to kill the "docker wait" process the regular paths will not be taken.
We lose a lot by running the container asynchronously with the dbuild shell
script, so we need to add it back:
- log display: via the "docker logs" command
- auto-removal of the container: add a "docker rm -f" command on signal
or normal exit
Message-Id: <20190424130112.794-1-avi@scylladb.com>
Official toolchain for ScyllaDB
While we aim to build out-of-the-box on recent distributions, this isn't always possible and not everyone runs a recent distribution. For this reason a version-controlled toolchain is provided as a docker image.
Quick start
If your workstation supports docker (without requiring sudo), you can build and run Scylla easily without setting up the build dependencies beforehand:
./tools/toolchain/dbuild ./configure.py
./tools/toolchain/dbuild ninja build/release/scylla
./tools/toolchain/dbuild ./build/release/scylla --developer-mode 1
The dbuild script
The script dbuild allows you to run any in that toolchain with
the working directory mounted:
./tools/toolchain/dbuild ./configure.py
./tools/toolchain/dbuild ninja
You can adjust the docker run command by adding more flags before the
command to be executed, separating the flags and the command with --.
This can be useful to attach more volumes (for data or ccache) and to
set environment variables:
./tools/toolchain/dbuild -v /var/cache/ccache:/var/cache/ccache -- ninja
The script also works from other directories, so if you have scylla-ccm checked
out alongside scylla, you can write
../scylla/tools/toolchain/dbuild ./ccm ...
You will have access to both scylla and scylla-ccm in the container.
Interactive mode is also supported, using the docker -i and -t flags:
./tools/toolchain/dbuild -it -- bash
this will drop you into a shell, with all of the toolchain accessible.
Obtaining the current toolchain
The toolchain is stored in a file called tools/toolchain/image. Normally,
dbuild will fetch the toolchain automatically. If you want to access
the toolchain explicitly, pull that image:
docker pull $(<tools/toolchain/image)
Building the toolchain
If you add dependencies (to install-dependencies.sh or
seastar/install-dependencies.sh) you should update the toolchain.
Run the command
docker build --no-cache -f tools/toolchain/Dockerfile .
and use the resulting image.
Publishing an image
If you're a maintainer, you can tag the image and push it
using docker push. Tags follow the format
scylladb/scylla-toolchain:fedora-29-[branch-3.0-]20181128. After the
image is pushed, update tools/toolchain/image so new
builds can use it automatically.
For master toolchains, the branch designation is omitted. In a branch, if there is a need to update a toolchain, the branch designation is added to the tag to avoid ambiguity.
Troubleshooting
When running sudo inside the container fails like this:
$ tools/toolchain/dbuild /bin/bash
bash-4.4$ sudo dnf install gdb
sudo: unknown uid 1000: who are you?
You can work it around by disabling SELinux on the host before running dbuild:
$ sudo setenforce 0