For jua infrastructure and model engineering teams
Jua weather training stalled: input pipeline or collective?
Compare loader progress, per-rank timing and the first exception. A visible NCCL wait may follow an upstream data failure rather than initiate it.
Free 30-day Team evaluation. No card or automatic subscription. Work email verification required.
Replay a resolved Jua workflow incident
Upload your log file. Review the selected evidence and masking, then run diagnosis. Keep the original log for any follow-up questions.
Before uploading, review cloud data handling and local options.
Upload your log file. Large files are processed in your browser. Only selected evidence is submitted when you run diagnosis.
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No credit card. No automatic subscription. See whether Denpex helps with an incident you already understand.
Start your free 30-day Team evaluation
Up to 50 diagnoses a day for 30 days. Verify your work email to activate an eligible company evaluation, then replay a resolved incident and compare the evidence and next steps with your team's confirmed cause.
What a useful evaluation should establish
Compare one incident your team has already resolved with the first failure, quoted evidence and remaining questions. Begin with this question: Did an input worker stop producing batches first? Only assign a process, device or recovery state when the submitted evidence establishes it.
Did an input worker stop producing batches first?
Evidence to compare: Loader queue depth, read errors and the corresponding training-step timestamps.
A training rank may wait because its next batch never arrived. Compare the input timeline before classifying a later collective timeout as a fabric fault.
Does the error match the configured parallelism?
Evidence to compare: Actual DDP or FSDP configuration and matched per-rank exceptions.
Memory allocation and synchronization have different boundaries across configurations. Preserve the deployed mode instead of recommending generic sharding changes.
Did requeue continue from a verified artifact?
Evidence to compare: Preemption event, checkpoint writer completion and resume input identity.
An automatic requeue can restart execution without proving recovery correctness. Confirm the artifact and successful continuation before calling the incident recovered.
Use Denpex alongside your existing telemetry tools to investigate submitted incident evidence. With monitoring configured on a supported plan, detected failures can trigger alerts and an automatic diagnosis from the captured evidence.
Inside Denpex
See the evidence, not just the claim
Follow the causal chain, inspect the quoted evidence and prepare the next handoff. These actual product captures use founder-account examples and the VS Code extension, with the source identified under each image. Open a capture to inspect it at full size.
Follow the failure through the cascade

Prepare the hardware escalation

Ask for the evidence that is missing

Keep the investigation in the editor
