Experiment Config Reference

A config file is needed when creating an experiment. This document describes the rules to write a config file and provides some examples.

Note

  1. This document lists field names with camelCase. If users use these fields in the pythonic way with NNI Python APIs (e.g., nni.experiment), the field names should be converted to snake_case.

  2. In this document, the type of fields are formatted as Python type hint. Therefore JSON objects are called dict and arrays are called list.

  1. Some fields take a path to a file or directory. Unless otherwise noted, both absolute path and relative path are supported, and ~ will be expanded to the home directory.

    • When written in the YAML file, relative paths are relative to the directory containing that file.

    • When assigned in Python code, relative paths are relative to the current working directory.

    • All relative paths are converted to absolute when loading YAML file into Python class, and when saving Python class to YAML file.

  2. Setting a field to None or null is equivalent to not setting the field.

Examples

Local Mode

experimentName: MNIST
searchSpaceFile: search_space.json
trialCommand: python mnist.py
trialCodeDirectory: .
trialGpuNumber: 1
trialConcurrency: 2
maxExperimentDuration: 24h
maxTrialNumber: 100
tuner:
  name: TPE
  classArgs:
    optimize_mode: maximize
trainingService:
  platform: local
  useActiveGpu: True

Local Mode (Inline Search Space)

searchSpace:
  batch_size:
    _type: choice
    _value: [16, 32, 64]
  learning_rate:
    _type: loguniform
    _value: [0.0001, 0.1]
trialCommand: python mnist.py
trialGpuNumber: 1
trialConcurrency: 2
tuner:
  name: TPE
  classArgs:
    optimize_mode: maximize
trainingService:
  platform: local
  useActiveGpu: True

Remote Mode

experimentName: MNIST
searchSpaceFile: search_space.json
trialCommand: python mnist.py
trialCodeDirectory: .
trialGpuNumber: 1
trialConcurrency: 2
maxExperimentDuration: 24h
maxTrialNumber: 100
tuner:
  name: TPE
  classArgs:
    optimize_mode: maximize
trainingService:
  platform: remote
  machineList:
    - host: 11.22.33.44
      user: alice
      password: xxxxx
    - host: my.domain.com
      user: bob
      sshKeyFile: ~/.ssh/id_rsa

Reference

ExperimentConfig

Field Name

Type

Description

experimentName

str, optional

Mnemonic name of the experiment, which will be shown in WebUI and nnictl.

searchSpaceFile

str, optional

Path to the JSON file containing the search space. Search space format is determined by tuner. The common format for built-in tuners is documented here. Mutually exclusive to searchSpace.

searchSpace

JSON, optional

Search space object. The format is determined by tuner. Common format for built-in tuners is documented here. Note that None means “no such field” so empty search space should be written as {}. Mutually exclusive to searchSpaceFile.

trialCommand

str

Command to launch trial. The command will be executed in bash on Linux and macOS, and in PowerShell on Windows. Note that using python3 on Linux and macOS, and using python on Windows.

trialCodeDirectory

str, optional

Default: ".". Path to the directory containing trial source files. All files in this directory will be sent to the training machine, unless in the .nniignore file. (See nniignore for details.)

trialConcurrency

int

Specify how many trials should be run concurrently. The real concurrency also depends on hardware resources and may be less than this value.

trialGpuNumber

int or None, optional

Default: None. This field might have slightly different meanings for various training services, especially when set to 0 or None. See training service’s document for details.

In local mode, setting the field to 0 will prevent trials from accessing GPU (by empty CUDA_VISIBLE_DEVICES). And when set to None, trials will be created and scheduled as if they did not use GPU, but they can still use all GPU resources if they want.

maxExperimentDuration

str, optional

Limit the duration of this experiment if specified. The duration is unlimited if not set. Format: number + s|m|h|d. Examples: "10m", "0.5h". When time runs out, the experiment will stop creating trials but continue to serve WebUI.

maxTrialNumber

int, optional

Limit the number of trials to create if specified. The trial number is unlimited if not set. When the budget runs out, the experiment will stop creating trials but continue to serve WebUI.

maxTrialDuration

str, optional

Limit the duration of trial job if specified. The duration is unlimited if not set. Format: number + s|m|h|d. Examples: "10m", "0.5h". When time runs out, the current trial job will stop.

nniManagerIp

str, optional

Default: default connection chosen by system. IP of the current machine, used by training machines to access NNI manager. Not used in local mode. Except for the local mode, it is highly recommended to set this field manually.

debug

bool, optional

Default: False. Enable debug mode. When enabled, logging will be more verbose and some internal validation will be loosened.

logLevel

str, optional

Default: info or debug, depending on debug option. Set log level of the whole system. values: "trace", "debug", "info", "warning", "error", "fatal" When debug mode is enabled, Loglevel is set to “debug”, otherwise, Loglevel is set to “info”. Most modules of NNI will be affected by this value, including NNI manager, tuner, training service, etc. The exception is trial, whose logging level is directly managed by trial code. For Python modules, “trace” acts as logging level 0 and “fatal” acts as logging.CRITICAL.

experimentWorkingDirectory

str, optional

Default: ~/nni-experiments. Specify the directory to place log, checkpoint, metadata, and other run-time stuff. NNI will create a subdirectory named by experiment ID, so it is safe to use the same directory for multiple experiments.

tunerGpuIndices

list[int] or str or int, optional

Limit the GPUs visible to tuner and assessor. This will be the CUDA_VISIBLE_DEVICES environment variable of tuner process. Because tuner and assessor run in the same process, this option will affect both of them.

tuner

AlgorithmConfig, optional

Specify the tuner. The built-in tuners can be found here and you can follow this tutorial to customize a new tuner.

assessor

AlgorithmConfig, optional

Specify the assessor. The built-in assessors can be found here and you can follow this tutorial to customize a new assessor.

advisor

AlgorithmConfig, optional

Deprecated, use tuner instead.

trainingService

TrainingServiceConfig

Specify the training service.

sharedStorage

SharedStorageConfig, optional

Configure the shared storage, detailed usage can be found here.

AlgorithmConfig

AlgorithmConfig describes a tuner / assessor / advisor algorithm.

For customized algorithms, there are two ways to describe them:

  1. Register the algorithm to use it like built-in. (preferred)

  2. Specify code directory and class name directly.

Field Name

Type

Description

name

str or None, optional

Default: None. Name of the built-in or registered algorithm, case insensitive. str for the built-in and registered algorithm, None for other customized algorithms.

className

str or None, optional

Default: None. Qualified class name of not registered customized algorithm. None for the built-in and registered algorithm, str for other customized algorithms. example: "my_tuner.MyTuner"

codeDirectory

str or None, optional

Default: None. Path to the directory containing the customized algorithm class. None for the built-in and registered algorithm, str for other customized algorithms.

classArgs

dict[str, Any], optional

Keyword arguments passed to algorithm class’ constructor. See algorithm’s document for supported value.

TrainingServiceConfig

One of the following:

LocalConfig

Introduction of the corresponding local training service can be found Local Training Service.

Field Name

Type

Description

platform

"local"

useActiveGpu

bool, optional

Default: False. Specify whether NNI should submit trials to GPUs occupied by other tasks. Must be set when trialGpuNumber greater than zero. Following processes can make GPU “active”:

  • non-NNI CUDA programs

  • graphical desktop

  • trials submitted by other NNI instances, if you have more than one NNI experiments running at same time

  • other users’ CUDA programs, if you are using a shared server

If you are using a graphical OS like Windows 10 or Ubuntu desktop, set this field to True, otherwise, the GUI will prevent NNI from launching any trial. When you create multiple NNI experiments and useActiveGpu is set to True, they will submit multiple trials to the same GPU(s) simultaneously.

maxTrialNumberPerGpu

int, optional

Default: 1. Specify how many trials can share one GPU.

gpuIndices

list[int] or str or int, optional

Limit the GPUs visible to trial processes. If trialGpuNumber is less than the length of this value, only a subset will be visible to each trial. This will be used as CUDA_VISIBLE_DEVICES environment variable.

RemoteConfig

Detailed usage can be found Remote Training Service.

Field Name

Type

Description

platform

"remote"

machineList

List[RemoteMachineConfig]

List of training machines.

reuseMode

bool, optional

Default: True. Enable reuse mode.

RemoteMachineConfig

Field Name

Type

Description

host

str

IP or hostname (domain name) of the machine.

port

int, optional

Default: 22. SSH service port.

user

str

Login user name.

password

str, optional

If not specified, sshKeyFile will be used instead.

sshKeyFile

str, optional

Path to sshKeyFile (identity file). Only used when password is not specified.

sshPassphrase

str, optional

Passphrase of SSH identity file.

useActiveGpu

bool, optional

Default: False. Specify whether NNI should submit trials to GPUs occupied by other tasks. Must be set when trialGpuNumber greater than zero. Following processes can make GPU “active”:

  • non-NNI CUDA programs

  • graphical desktop

  • trials submitted by other NNI instances, if you have more than one NNI experiments running at same time

  • other users’ CUDA programs, if you are using a shared server

If your remote machine is a graphical OS like Ubuntu desktop, set this field to True, otherwise, the GUI will prevent NNI from launching any trial. When you create multiple NNI experiments and useActiveGpu is set to True, they will submit multiple trials to the same GPU(s) simultaneously.

maxTrialNumberPerGpu

int, optional

Default: 1. Specify how many trials can share one GPU.

gpuIndices

list[int] or str or int, optional

Limit the GPUs visible to trial processes. If trialGpuNumber is less than the length of this value, only a subset will be visible to each trial. This will be used as CUDA_VISIBLE_DEVICES environment variable.

pythonPath

str, optional

Specify a Python environment. This path will be inserted at the front of PATH. Here are some examples:

  • (linux) pythonPath: /opt/python3.7/bin

  • (windows) pythonPath: C:/Python37

If you are working on Anaconda, there is some difference. On Windows, you also have to add ../script and ../Library/bin separated by ;. Examples are as below:

  • (linux anaconda) pythonPath: /home/yourname/anaconda3/envs/myenv/bin/

  • (windows anaconda) pythonPath: C:/Users/yourname/.conda/envs/myenv; C:/Users/yourname/.conda/envs/myenv/Scripts; C:/Users/yourname/.conda/envs/myenv/Library/bin

This is useful if preparing steps vary for different machines.

OpenpaiConfig

Detailed usage can be found here.

Field Name

Type

Description

platform

"openpai"

host

str

Hostname of OpenPAI service. This may include https:// or http:// prefix. HTTPS will be used by default.

username

str

OpenPAI user name.

token

str

OpenPAI user token. This can be found in your OpenPAI user settings page.

trialCpuNumber

int

Specify the CPU number of each trial to be used in OpenPAI container.

trialMemorySize

str

Specify the memory size of each trial to be used in OpenPAI container. format: number + tb|gb|mb|kb. examples: "8gb", "8192mb".

storageConfigName

str

Specify the storage name used in OpenPAI.

dockerImage

str, optional

Default: "msranni/nni:latest". Name and tag of docker image to run the trials.

localStorageMountPoint

str

Mount point of storage service (typically NFS) on the local machine.

containerStorageMountPoint

str

Mount point of storage service (typically NFS) in docker container. This must be an absolute path.

reuseMode

bool, optional

Default: True. Enable reuse mode.

openpaiConfig

JSON, optional

Embedded OpenPAI config file.

openpaiConfigFile

str, optional

Path to OpenPAI config file. An example can be found here.

AmlConfig

Detailed usage can be found here.

Field Name

Type

Description

platform

"aml"

dockerImage

str, optional

Default: "msranni/nni:latest". Name and tag of docker image to run the trials.

subscriptionId

str

Azure subscription ID.

resourceGroup

str

Azure resource group name.

workspaceName

str

Azure workspace name.

computeTarget

str

AML compute cluster name.

DlcConfig

Detailed usage can be found here.

Field Name

Type

Description

platform

"dlc"

type

str, optional

Default: "Worker". Job spec type.

image

str

Name and tag of docker image to run the trials.

jobType

str, optional

Default: "TFJob". PAI-DLC training job type, "TFJob" or "PyTorchJob".

podCount

str

Pod count to run a single training job.

ecsSpec

str

Training server config spec string.

region

str

The region where PAI-DLC public-cluster locates.

nasDataSourceId

str

The NAS datasource id configurated in PAI-DLC side.

ossDataSourceId

str

The OSS datasource id configurated in PAI-DLC side, this is optional.

accessKeyId

str

The accessKeyId of your cloud account.

accessKeySecret

str

The accessKeySecret of your cloud account.

localStorageMountPoint

str

The mount point of the NAS on PAI-DSW server, default is /home/admin/workspace/.

containerStorageMountPoint

str

The mount point of the NAS on PAI-DLC side, default is /root/data/.

HybridConfig

Currently only support LocalConfig, RemoteConfig, OpenpaiConfig and AmlConfig . Detailed usage can be found here.

SharedStorageConfig

Detailed usage can be found here.

NfsConfig

Field Name

Type

Description

storageType

"NFS"

localMountPoint

str

The path that the storage has been or will be mounted in the local machine. If the path does not exist, it will be created automatically. Recommended to use an absolute path, i.e. /tmp/nni-shared-storage.

remoteMountPoint

str

The path that the storage will be mounted in the remote machine. If the path does not exist, it will be created automatically. Recommended to use a relative path. i.e. ./nni-shared-storage.

localMounted

str

Specify the object and status to mount the shared storage. values: "usermount", "nnimount", "nomount" usermount means the user has already mounted this storage on localMountPoint. nnimount means NNI will try to mount this storage on localMountPoint. nomount means storage will not mount in the local machine, will support partial storages in the future.

nfsServer

str

NFS server host.

exportedDirectory

str

Exported directory of NFS server, detailed here.

AzureBlobConfig

Field Name

Type

Description

storageType

"AzureBlob"

localMountPoint

str

The path that the storage has been or will be mounted in the local machine. If the path does not exist, it will be created automatically. Recommended to use an absolute path, i.e. /tmp/nni-shared-storage.

remoteMountPoint

str

The path that the storage will be mounted in the remote machine. If the path does not exist, it will be created automatically. Recommended to use a relative path. i.e. ./nni-shared-storage. Note that the directory must be empty when using AzureBlob.

localMounted

str

Specify the object and status to mount the shared storage. values: "usermount", "nnimount", "nomount". usermount means the user has already mounted this storage on localMountPoint. nnimount means NNI will try to mount this storage on localMountPoint. nomount means storage will not mount in the local machine, will support partial storages in the future.

storageAccountName

str

Azure storage account name.

storageAccountKey

str

Azure storage account key.

containerName

str

AzureBlob container name.