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dockerdocker-composedocker-swarm

Setting Docker's deploy.resources.limits.cpus with an unknown number of cores?

It's plausible that machines in a cluster have different numbers of cores. Docker Swarm mode's deploy.resources.limits.cpus config specifies the absolute number of cores. Is it possible to specify a percentage of the total available CPU resources? I want the total CPU limit to be close to 100% of the max capacity.

dockerfile snippet:

deploy:
  resources:
    limits:
      cpus: '1'
      memory: 4G
Solution

  • no.

    If you have a service that actually can benefit from multiple cores, set the cpu limit to the a reasonable common divisor of the min and max cores your nodes have available, and then just set the replicas to a number such that deploy.replicas * deploy.resource.limits.cpus ~= total-swarm-cpus.