根据可用CPU核数扩展docker服务

我想到的一个选择是定期检查连接的节点,并为每个节点创建具有适当数量副本的服务。这可能不是一个非常优雅的解决方案,但至少可以与以下Python脚本一起使用。

#!/usr/bin/env python3

import docker

def rescale(service_prefix,service_arguments):
    client = docker.from_env()
    service_names = [s.name for s in client.services.list()]

    for node in client.nodes.list():
        # Only handle ready nodes
        if node.attrs['Status']['State'] != 'ready':
            continue

        service_name = service_prefix+node.id
        if service_name not in service_names:
            # Service does not exist -> Create it
            cpus = node.attrs['Description']['Resources']['NanoCPUs']/1000000000
            print("Creating service %s with %i replicas"%(service_name,cpus))
            mode={'Replicated':{'Replicas':int(cpus)}}
            constraints=['node.id==%s'%node.id]
            client.services.create(name=service_name, mode=mode, constraints=constraints, **service_arguments)
        else:
            # Continue running this service
            service_names.remove(service_name)

    # Remove services of no longer existing nodes
    for service in service_names:
        print("Removing service %s"%service)
        client.services.get(service).remove()

rescale(service_prefix="evaluation_",
        service_arguments={'image':'imagename','networks':['swarmnet']})