Avoid deadlocks under heavy load, especially during index node startup #6224
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This helps us avoid timeouts when we encounter a thundering herd, for example when an index node starts up and all subgraphs want access to the database.
The start_subgraph code called load_indexes while holding a connection; load_indexes tries to get another connection. If the pool is exhausted because many subgraphs are starting, we end up in a deadlock.
isum
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Dec 9, 2025
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tokio-postgres does not respect PGAPPNAME, so that its connections are not named properly in pg_stat_activity etc. We manually add it to the URL to help tracking and debugging connection issues
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