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If wandb crashes, will it possibly crash my training run?

It is extremely important to us that we never interfere with your training runs. We run wandb in a separate process to make sure that if wandb somehow crashes, your training will continue to run. If the internet goes out, wandb will continue to retry sending data to

Why is a run marked crashed in W&B when it’s training fine locally?

This is likely a connection problem — if your server loses internet access and data stops syncing to W&B, we mark the run as crashed after a short period of retrying.

Does logging block my training?

"Is the logging function lazy? I don't want to be dependent on the network to send the results to your servers and then carry on with my local operations."

Calling wandb.log writes a line to a local file; it does not block any network calls. When you call wandb.init we launch a new process on the same machine that listens for filesystem changes and talks to our web service asynchronously from your training process.

How do I stop wandb from writing to my terminal or my jupyter notebook output?

Set the environment variable WANDB_SILENT to true.

os.environ["WANDB_SILENT"] = "true"

How do I kill a job with wandb?

Press Ctrl+D on your keyboard to stop a script that is instrumented with wandb.

How do I deal with network issues?

If you're seeing SSL or network errors:wandb: Network error (ConnectionError), entering retry loop. You can try a couple of different approaches to solving this issue:

  1. Upgrade your SSL certificate. If you're running the script on an Ubuntu server, run update-ca-certificates We can't sync training logs without a valid SSL certificate because it's a security vulnerability.
  2. If your network is flaky, run training in offline mode and sync the files to us from a machine that has Internet access.
  3. Try running W&B Private Hosting, which operates on your machine and doesn't sync files to our cloud servers.

SSL CERTIFICATE_VERIFY_FAILED: this error could be due to your company's firewall. You can set up local CAs and then use:

export REQUESTS_CA_BUNDLE=/etc/ssl/certs/ca-certificates.crt

What happens if internet connection is lost while I'm training a model?

If our library is unable to connect to the internet it will enter a retry loop and keep attempting to stream metrics until the network is restored. During this time your program is able to continue running.

If you need to run on a machine without internet, you can set WANDB_MODE=offline to only have metrics stored locally on your hard drive. Later you can call wandb sync DIRECTORY to have the data streamed to our server.

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