Incident: Search Failures

Starting at 8:15 PM PDT on October 21, 2025, until around 1:00 AM PDT on October 22, 2025, some users may have experienced partial search results when querying items in Slack.A backend change unexpectedly initiated a restart job for some services responsible for handling searches. These jobs inadvertently caused the search processing capacity to become temporarily overwhelmed, creating a large backlog of queries. To help mitigate this, we performed a restart of the relevant indexing processes, which fully restored search functionality for all affected users.A subset of users affected by the backlog may have encountered ongoing partial search results, we outlined the related incident here: https://slack-status.com/2025-10/65f3383a2d6aebdf.