update docs

Author: ayulockin

website/docs/notes/logging.md

@@ -1,42 +1,75 @@
 ---
-id: concepts
-title: Terminology and Concepts
-sidebar_label: Terminology and Concepts
+id: logger
+title: Weights and Biases Logging
+sidebar_label: Weights and Biases Logging
 ---
 
 ## Weights and Biases Logger
 
-MMF has a `WandbLogger` class which lets the user to log their model's progress using [Weights and Biases](https://gitbook-docs.wandb.ai/).
+MMF now has a `WandbLogger` class which lets the user to log their model's progress using [Weights and Biases](https://wandb.ai/site). Enable this logger to automatically log the training/validation metrics, system (GPU and CPU) metrics and configuration parameters.
+
+## First time setup 
 
 To set up wandb, run the following:
 ```
 pip install wandb
+```
+In order to log anything to the W&B server you need to authenticate the machine with W&B **API key**. You can create a new account by going to https://wandb.ai/signup which will generate an API key. If you are an existing user you can retrieve your key from https://wandb.ai/authorize. You only need to supply your key once, and then it is remembered on the same device. 
+
+```
 wandb login
 ```
 
+## W&B config parameters
+
 The following options are available in config to enable and customize the wandb logging:
 ```yaml
 training:
     # Weights and Biases control, by default Weights and Biases (wandb) is disabled
     wandb:
         # Whether to use Weights and Biases Logger, (Default: false)
         enabled: false
+        # An entity is a username or team name where you're sending runs.
+        # This is necessary if you want to log your metrics to a team account. By default
+        # it will log the run to your user account.
+        entity: null
         # Project name to be used while logging the experiment with wandb
-        wandb_projectname: mmf_${oc.env:USER}
+        wandb_projectname: mmf_${oc.env:USER,}
         # Experiment/ run name to be used while logging the experiment
         # under the project with wandb
         wandb_runname: ${training.experiment_name}
+        # Specify other argument values that you want to pass to wandb.init(). Check out the documentation
+        # at https://docs.wandb.ai/ref/python/init to see what arguments are available.
+        # job_type: 'train'
+        # tags: ['tag1', 'tag2']
 env:
     wandb_logdir: ${env:MMF_WANDB_LOGDIR,}
-```
-To enable wandb logger the user needs to change the following option in the config.
+``` 
+
+* To enable wandb logger the user needs to change the following option in the config.
+
+	`training.wandb.enabled=True`
+
+* To give the `entity` which is the name of the team or the username, the user needs to change the following option in the config. In case no `entity` is provided, the data will be logged to the `entity` set as default in the user's settings. 
+
+	`training.wandb.entity=<teamname/username>`
+
+* To give the current experiment a project and run name, user should add these config options.
+
+	`training.wandb.wandb_projectname=<ProjectName>` <br>
+	`training.wandb.wandb_runname=<RunName>`
+
+* To change the path to the directory where wandb metadata would be stored (Default: `env.log_dir`):
 
-`training.wandb.enabled=True`
+	`env.wandb_logdir=<dir_name>`
 
-To give the current experiment a project and run name, user should add these config options.
+* To provide extra arguments to `wandb.init()`, the user just needs to define them in the config file. Check out the documentation at https://docs.wandb.ai/ref/python/init to see what arguments are available. An example is shown in the config parameter shown above. 
 
-`training.wandb.wandb_projectname=<ProjectName> training.wandb.wandb_runname=<RunName>`
+## Current features
 
-To change the path to the directory where wandb metadata would be stored (Default: `env.log_dir`):
+The following features are currently supported by the `WandbLogger`:
 
-`env.wandb_logdir=<dir_name>`
+* Training & Validation metrics
+* Learning Rate over time
+* GPU: Type, GPU Utilization, power, temperature, CUDA memory usage
+* Log configuration parameters