Find the slow task in a Mammoth pipeline and get help
To find what slows a pipeline, check the row count at each task, then watch running work in Monitor in the left sidebar. If it's still slow after the fixes in Speed up Mammoth pipelines, contact support with the details below.
Find the slow task in a pipeline
Use Preview Data at this Task on each task to see the row count at that point. Look for:
- tasks where the row count is higher than you expect (a filter that should cut rows but doesn't)
- tasks that work across the whole dataset, such as joins and Group & Pivot on large datasets
- Math Function columns with complex calculations across millions of rows
Then apply the matching fix:
| What you find | Fix |
|---|---|
| Row counts stay high | Move Conditional Filter tasks as early as possible, ideally right after the source |
| A slow Join | Check whether Lookup is enough, and whether the join key has duplicates |
| Many unused columns | Add a Remove Column task right after the source |
| Heavy rebuilds while you edit | Turn on Draft mode |
Watch running work in Monitor
Open Monitor in the left sidebar. You don't need to stay on the page, because Mammoth runs processing on its servers.
| Tab | What it shows |
|---|---|
| Needs Attention | Errors, pending data, and governance items (pipeline checkpoints, failed data checks) waiting on you |
| Running | Pipelines, tasks and automations running or queued. A task that runs unusually long is flagged Stuck |
| Paused | Pipeline tasks, exports and connections with Auto-sync off |
| Activity Log | A history of events, if your role has activity log access |
See Monitor running, failing and paused pipelines and Activity log.
Limits that affect performance
Storage is set by your plan: see Workspace Settings → Plan & Storage for your allowance and per-dataset usage. Uploads from your computer are limited to 50 MB per request, and BI workbook imports (Tableau .twbx, Power BI .pbix) to 1 GB. A BigQuery query times out after 5 minutes, and a long-running job after 1 hour; contact Mammoth support if a connector's timeout interrupts your work. Contact your account team for the limits that apply to your workspace and plan, and see Limits and quotas.
Still slow? Contact support
- Check Monitor: Running shows whether a task is Stuck, and Needs Attention lists failed runs and errors.
- Find the slowest task. Joins are the most common culprit: check them for duplicate keys, because fan-out multiplies rows.
- Move any Conditional Filter tasks earlier.
- Email support@mammoth.io. Support can inspect server-side run logs. Include:
- your workspace name and dataset name
- the View's name and the slow task (or the pipeline ID)
- the approximate row count and column count
- the operation that's slow (dashboard load, pipeline run, export, automation)
- how long it takes, and how long you'd expect
Related
- Speed up Mammoth pipelines: filter early, order tasks and use Draft mode.
- Speed up refreshes and exports: when a refresh, not the pipeline, is slow.
- Fix connection and refresh failures: when a refresh fails instead of running slowly.
Something wrong? support@mammoth.io