AliECS

The ALICE Experiment Control System (AliECS) is the piece of software to drive and control data taking activities in the experiment. It is a distributed system that combines state of the art cluster resource management and experiment control functionalities into a single comprehensive solution.

Please refer to the CHEP 2023 paper for the latest design overview.

How to get started

Regardless of your particular interests, it is recommended to get acquainted with the main AliECS concepts.

After that, please find your concrete use case:

I want to run AliECS and other O²/FLP software

See O²/FLP Suite deployment instructions

These instructions apply to both single-node and multi-node deployments. Contact alice-o2-flp-support for assistance with provisioning and deployment.

There are two ways of interacting with AliECS:

• The AliECS GUI (a.k.a. Control GUI, COG) - not in this repository, but included in most deployments, recommended

  ➡️ AliECS GUI documentation

• coconut - the command-line control and configuration utility, included with AliECS core, typically for developers and advanced users

  ➡️ Using coconut

  ➡️ coconut command reference

I want to ensure AliECS can run and control my process

• My software is based on FairMQ and/or O² DPL (Data Processing Later)

  AliECS natively supports FairMQ (and DPL) devices. Head to ControlWorkflows for instructions on how to configure your software to be controlled by AliECS.

• My software does not use FairMQ and/or DPL, but should be controlled through a state machine

  See the OCC documentation to learn how to integrate the O² Control and Configuration library with your software. Readout is an example of this setup.

  Once ready, head to ControlWorkflows for instructions on how to configure it to be controlled by AliECS.

• My software is a command line utility with no state machine

  AliECS natively supports generic commands. Head to ControlWorkflows for instructions to have your command ran by AliECS. Make sure the task template for your command sets the control mode to basic (see example).

I want to develop AliECS

🛠️ Welcome to the team, please head to contributing instructions

I want to receive updates about environments or services controlled by AliECS

📟 Learn more about the kafka event service

I want my application to send requests to AliECS

📜 See the API docs of AliECS components:

• core gRPC server
• apricot gRPC server
• apricot HTTP server

I want my service to be sent requests by AliECS

🔌 Learn more about the plugin system

Table of Contents

• Introduction

  • Basic Concepts
    • Tasks
    • Workflows, roles and environments
  • Design Overview
    • AliECS Structure
    • Resource Management
    • FairMQ
    • State machines

• Component reference

  • AliECS GUI
    • AliECS GUI overview
  • AliECS core
    • Workflow Configuration
      • The AliECS workflow template language
      • Workflow template structure
        • Task roles
        • Call roles
        • Aggregator roles
        • Iterator roles
        • Include roles
        • Template expressions
    • Task Configuration
      • Task template structure
      • Variables pushed to controlled tasks
      • Resource wants and limits
    • Integration plugins
      • Plugin system overview
    • Integrated service operations
      • Bookkeeping
      • CCDB
      • DCS
        • DCS operations
        • DCS PrepareForRun behaviour
        • DCS StartOfRun behaviour
        • DCS EndOfRun behaviour
        • ECS2DCS2ECS mock server
      • DD Scheduler
      • Kafka (legacy)
      • ODC
      • Test plugin
      • Trigger
    • Environment operation order
      • State machine triggers
      • START_ACTIVITY (Start Of Run)
      • STOP_ACTIVITY (End Of Run)
    • Protocol documentation
  • coconut
    • The O² control and configuration utility overview
      • Configuration file
      • Using coconut
        • Creating an environment
        • Controlling an environment
    • Command reference
  • apricot
    • ALICE configuration service overview
    • HTTP service
      • Configuration
      • Usage and options
      • Examples
    • Protocol documentation
    • Command reference
  • occ
    • O² Control and Configuration Components
      • Developer quick start instructions for OCClib
      • Manual build instructions
      • Run example
      • The OCC state machine
      • Single process control with peanut
      • OCC API debugging with grpcc
    • Dummy process example for OCC library
    • Protocol documentation
  • peanut
    • Process control and execution utility overview
  • Event service
    • Kafka producer functionality in AliECS core
      • Making sure that AliECS sends messages
      • Currently available topics
      • Decoding the messages
    • Legacy events: Kafka plugin
      • Making sure that AliECS sends messages
      • Currently available topics
      • Decoding the messages
      • Getting Start of Run and End of Run notifications
      • Using Kafka debug tools

• Developer documentation

  • Contributing
  • Package pkg.go.dev documentation
  • Building AliECS
    • Overview
    • Building with aliBuild
    • Manual build
      • Go environment
      • Clone and build (Go components only)
  • Makefile reference
  • Component Configuration
    • Apache Mesos
      • Connectivity to controlled nodes
  • Running AliECS as a developer
    • Running the AliECS core
  • Running AliECS in production
    • Health checks
  • Development Information
    • Release Procedure
  • Metrics in ECS
    • Overview and simple usage
    • Types and aggregation of metrics
      • Metric types
      • Aggregation
    • Implementation details
      • Event loop
      • Hashing to aggregate
      • Sampling reservoir
  • OCC API debugging with grpcc

• Resources

  • T. Mrnjavac et. al, AliECS: A New Experiment Control System for the ALICE Experiment, CHEP23