<!--IssueSummary start--> <details> <summary> Everyone can contribute. [Help move this issue forward](https://handbook.gitlab.com/handbook/marketing/developer-relations/contributor-success/community-contributors-workflows/#contributor-links) while earning points, leveling up and collecting rewards. </summary> - [Close this issue](https://contributors.gitlab.com/manage-issue?action=close&projectId=278964&issueIid=585531) </details> <!--IssueSummary end--> Limit the number of processing `BulkImports::Export` records for offline transfer exports to prevent system strain from concurrent offline transfer exports. ## Recommended implementation Limit the number of `BulkImports::Export` in `started` state with the same `offline_export_id` to similar to the [max number of entities processing in direct transfer](https://gitlab.com/gitlab-org/gitlab/-/blob/master/app/services/bulk_imports/process_service.rb#L6). Note that one entity in direct transfer would be akin to all relation exports for a single portable in offline transfer exports. If the limit of processing relation exports has been exceeded, re-enqueue the worker. ## Related - Broken out from Create offline transfer export worker (#576092) - Offline transfer ADR: https://handbook.gitlab.com/handbook/engineering/architecture/design-documents/offline_direct_transfer_migrations/