893d4a77c8
The allocrunner sends several updates to the server during the early lifecycle of an allocation and its tasks. Clients batch-up allocation updates every 200ms, but experiments like the C2M challenge has shown that even with this batching, servers can be overwhelmed with client updates during high volume deployments. Benchmarking done in #9451 has shown that client updates can easily represent ~70% of all Nomad Raft traffic. Each allocation sends many updates during its lifetime, but only those that change the `ClientStatus` field are critical for progressing a deployment or kicking off a reschedule to recover from failures. Add a priority to the client allocation sync and update the `syncTicker` receiver so that we only send an update if there's a high priority update waiting, or on every 5th tick. This means when there are no high priority updates, the client will send updates at most every 1s instead of 200ms. Benchmarks have shown this can reduce overall Raft traffic by 10%, as well as reduce client-to-server RPC traffic. This changeset also switches from a channel-based collection of updates to a shared buffer, so as to split batching from sending and prevent backpressure onto the allocrunner when the RPC is slow. This doesn't have a major performance benefit in the benchmarks but makes the implementation of the prioritized update simpler. Fixes: #9451
Nomad
Nomad is a simple and flexible workload orchestrator to deploy and manage containers (docker, podman), non-containerized applications (executable, Java), and virtual machines (qemu) across on-prem and clouds at scale.
Nomad is supported on Linux, Windows, and macOS. A commercial version of Nomad, Nomad Enterprise, is also available.
- Website: https://nomadproject.io
- Tutorials: HashiCorp Learn
- Forum: Discuss
Nomad provides several key features:
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Deploy Containers and Legacy Applications: Nomad’s flexibility as an orchestrator enables an organization to run containers, legacy, and batch applications together on the same infrastructure. Nomad brings core orchestration benefits to legacy applications without needing to containerize via pluggable task drivers.
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Simple & Reliable: Nomad runs as a single binary and is entirely self contained - combining resource management and scheduling into a single system. Nomad does not require any external services for storage or coordination. Nomad automatically handles application, node, and driver failures. Nomad is distributed and resilient, using leader election and state replication to provide high availability in the event of failures.
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Device Plugins & GPU Support: Nomad offers built-in support for GPU workloads such as machine learning (ML) and artificial intelligence (AI). Nomad uses device plugins to automatically detect and utilize resources from hardware devices such as GPU, FPGAs, and TPUs.
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Federation for Multi-Region, Multi-Cloud: Nomad was designed to support infrastructure at a global scale. Nomad supports federation out-of-the-box and can deploy applications across multiple regions and clouds.
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Proven Scalability: Nomad is optimistically concurrent, which increases throughput and reduces latency for workloads. Nomad has been proven to scale to clusters of 10K+ nodes in real-world production environments.
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HashiCorp Ecosystem: Nomad integrates seamlessly with Terraform, Consul, Vault for provisioning, service discovery, and secrets management.
Quick Start
Testing
See Learn: Getting Started for instructions on setting up a local Nomad cluster for non-production use.
Optionally, find Terraform manifests for bringing up a development Nomad cluster on a public cloud in the terraform directory.
Production
See Learn: Nomad Reference Architecture for recommended practices and a reference architecture for production deployments.
Documentation
Full, comprehensive documentation is available on the Nomad website: https://www.nomadproject.io/docs
Guides are available on HashiCorp Learn.
Roadmap
A timeline of major features expected for the next release or two can be found in the Public Roadmap.
This roadmap is a best guess at any given point, and both release dates and projects in each release are subject to change. Do not take any of these items as commitments, especially ones later than one major release away.
Contributing
See the contributing directory for more developer documentation.