m3em/

m3em

m3em (pronounced meme) is an acronym for M3 Environment Manager. ccm:C* :: m3em:m3db. Unlike ccm, m3em permits remote host operations.

The goal of m3em is to make it easy to create, manage and destroy services across hosts. It is meant for testing clustered services like m3db and m3aggregator .

Components

There are two primary components in m3em:

(1) API constructs encapsulating placement interactions (see cluster package), along with remote process orchestration (see node package).

(2) m3em_agent: process running on remote hosts. It's responsible for process lifecycle, heartbeating back to the coordinating host.

Usage Example

• For API usage, refer tools/dtest in M3DB

m3em_agent

$ make m3em_agent
$ scp ./out/m3em_agent <remote-host>:<remote-path>
$ ssh <remote-host>
$ cat >m3em.agent.yaml <<EOF
server:
  listenAddress: "0.0.0.0:14541"
  debugAddress: "0.0.0.0:24541"

metrics:
  sampleRate: 0.02
  m3:
    hostPort: "127.0.0.1:9052"
    service: "m3em"
    includeHost: true
    env: "development"

agent:
  workingDir: /var/m3em-agent
  startupCmds:
    - path: /bin/echo
      args:
        - "sample startup command"
  releaseCmds:
    - path: /bin/echo
      args:
        - "sample release command"
  testEnvVars:
    UBER_DATACENTER: sjc1
EOF
$ /remote-path/m3em_agent -f m3em.agent.yaml