The example configuration project for buildbarn
bb-deployments
has gotten updates.
This is a continuation of the
updates from last year article
and is a high level summary of what has happened since April 2022 up to 2023-02-16.
Let ReferenceExpandingBlobAccess support GCS
ReferenceExpandingBlobAccess already supports S3 so support was extended to Google Cloud Storage buckets.
Support for prefetching Virtual Filesystems
Running workers with Fuse allows inputs for an action
to be downloaded on demand.
This significantly reduces the amount of data
that gets sent in order to run overspecified actions.
This however leads to poor performance for actions
which reads a lot of their inputs synchronously.
With the prefetcher most of these actions can be recognized
and data which is likely to be needed
can be downloaded ahead of time.
Support for sha256tree
Buildbarn has added support for
sha256tree
which uses sha256 hashing over a tree structure similar to blake3.
This algorithm will allow large CAS objects to be chunked and decompositioned
with guaranteed data integrity while still using sha256 hardware instructions.
Completeness checking now streams REv2 Tree objects
This change introduces a small change to the configuration schema. If you previous had this:
backend: { completenessChecking: ... },
You will now need to write something along these lines:
backend: {
completenessChecking: {
backend: ...,
maximumTotalTreeSizeBytes: 64 * 1024 * 1024,
},
},
See also the
bb-storage commit 1b84fa8.
Postponed healthy service status
The healthy and serving status,
i.e. HTTP /-/healthy and
grpc_health_v1.HealthCheckResponse_SERVING,
are now postponed until the whole service is up and running.
Before, the healthy status was potentially reported before starting to listen to the gRPC ports.
Kubernetes will now wait until the service is up before forwarding connections to it.
Server keepalive parameter options
The option buildbarn.configuration.grpc.ServerConfiguration.keepalive_parameters can be used for L4 load balancing,
to control when to ask clients to reconnect.
For default values, see
keepalive.ServerParameters.
Graceful termination of LocalBlobAccess
When SIGTERM or SIGINT is received, the LocalBlobAccess now synchronize data to disk before shutting down.
Deployments using persistent storage will no longer observe loss of data when restarting the bb_storage services.
Non-sector Aligned Writes to Block Device
Using sector aligned storage is wasteful for the action cache where the messages are typically very small.
Buildbarn can now fill all the gaps when writing, making storage more efficient.
DAG Shaped BlobAccess Configuration
Instead of a tree shaped BlobAccess configuration, the with_labels notation allows a directed acyclic graph.
See also the
bb-storage commit cc295ad.
NFSv4 as worker filesystem
The bb_worker can now supply the working directory for bb_runner using NFSv4.
Previously, FUSE and hard linking files from the worker cache were the only two options.
This addition was mainly done to overcome the poor FUSE support on macOS.
The NFSv4 server in bb_worker only supports macOS at the moment.
No effort has been spent to write custom mount logic for other systems yet.
Metadata forwarding is now more flexible, the JMESPath expressions can for example add authorization result data.
The format is described in
grpc.proto.
A common use case is to replace
{
forwardMetadata: ["build.bazel.remote.execution.v2.requestmetadata-bin"],
}
with
{
addMetadataJmespathExpression: '{
"build.bazel.remote.execution.v2.requestmetadata-bin":
incomingGRPCMetadata."build.bazel.remote.execution.v2.requestmetadata-bin"
}',
}
Tracing: Deprecate the Jaeger collector span exporter
This option is deprecated, as Jaeger 1.35 and later provide native support for the OpenTelemetry protocol.
bb-deployments Ubuntu 22.04 Example Runner Image
The rbe_autoconfig
in bazel-toolchains
has been deprecated. In bb-deployments it has been replaced by the
Act image
ghcr.io/catthehacker/ubuntu:act-22.04,
distributed by catthehacker,
used for running GitHub Actions locally under Ubuntu 22.04.
bb-deployments Integration Tests
The bare deployment and
Docker Compose deployment
have now got tests scripts
that builds and tests @abseil-hello//:hello_test remotely, shuts down and then checks for 100% cache hit after restart.
Another CI test is checking for minimal differences between the Docker Compose deployment and
the Kubernetes deployment.
If there are any other changes you feel deserve a mention
feel free to submit a pull request at github using the link below.