# Dagster: Major incident: Issues with global op concurrency keys

**Summary:** Dagster reported a major API and Dagster Cloud UI degradation from 2025-02-07 15:37 UTC to 2025-02-07 16:11 UTC (34 min): some runs with concurrency keys lacking explicit configuration or a default limit were blocked, and concurrency settings had UI issues. Fixes restored progress, but previously blocked runs might still require manual termination. _(machine-written, sol)_
- Kind: Major incident · Label: degradation (model (Jev))
- Changed: 2025-02-07 15:37 UTC · Detected: 2026-10-17 18:22 UTC
- [Source: https://stspg.io/qwy8xbj9g7fz](https://stspg.io/qwy8xbj9g7fz)
- [Company: Dagster](https://rewindex.com/company/dagster.md)
- Versions: before (none: first archived) → after incident\_version:141/31ddm3csbjx1@e30774e2cec9
- Change 1 of 1 for this incident

## What changed

**1. Added: Title**

```diff
+ Issues with global op concurrency keys
```

**2. Added: Impact**

```diff
+ major
```

**3. Added: Status**

```diff
+ resolved
```

**4. Added: Start time**

```diff
+ 2025-02-07 15:37 UTC
```

**5. Added: Resolved time**

```diff
+ 2025-02-07 16:11 UTC
```

**6. Added: Affected components**

```diff
+ API, Dagster Cloud UI
```

**7. Added: Update** (identified) · 2025-02-07 15:37 UTC

```diff
+ Some runs containing ops tagged with concurrency keys that have not been configured explicitly or with a default limit are getting blocked. Separately, there are some UI issues affecting the concurrency key settings page.  We have identified fixes for these and are in the process of rolling them out.
```

**8. Added: Update** (monitoring) · 2025-02-07 15:56 UTC

```diff
+ The fixes has been rolled out and previously blocked runs appear to be progressing.  We are continuing to monitor for any issues. The previous blocked runs should progress with their step execution, but may not reach a terminal state and may need to be manually terminated.
```

**9. Added: Update** (resolved) · 2025-02-07 16:11 UTC

```diff
+ This incident has been resolved.
```

## History of this incident

| When (UTC) | Change | Label |
| --- | --- | --- |
| 2025-02-07 15:37 UTC | Major incident: Issues with global op concurrency keys (this change) | degradation |

All Dagster changes: [timeline](https://rewindex.com/company/dagster/changes.md)
_Diff excerpts are shown on normalized text: dates, counters and tokens appear as ‹date›, ‹count›, ‹tok›; noise-only edits are hidden. Rewindex shows the changed passages, not a copy of the page._


---
Canonical: https://rewindex.com/change/i757b85ca89b318 · Markdown: https://rewindex.com/change/i757b85ca89b318.md · JSON: https://rewindex.com/api/v1/changes/i757b85ca89b318 · Generated 2026-10-18T01:30:14.604Z