storage: in storage_collections, halt when we have to mint new IDs in… #33338
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… read-only mode Before, this scenario could happen when starting two deploy generations for the same environment concurrently: 1. Gen 1 bootstraps and sets up catalog state just enough, without minting global id -> shard id mappings. 2. Gen 2 bootstraps, notices that the catalog state already exists and that it is gen 2 but catalog state is from gen 1. Because of this is starts in read-only mode. In https://github.com/MaterializeInc/materialize/blob/e3c1b3b3620ea6d6c619f59efbfada11a5575ecb/src/storage-client/src/storage_collections.rs#L1384, we mint new shard ID mappings, which will go into ephemeral catalog state because we're in read-only mode. 3. Gen 1 gets around to mint global id -> shard id mappings and writes them down durably, then starts to proceed with bootstrap. 4. Gen 2 is waiting for collections to hydrate that never do, because no-one ever advances their frontiers. It never reports as ready to promote, so tests that expect this will hang. This isn't a correctness issue, the environment will hang forever or hit a timeout, halt, and restart, at which point it sees the catalog state with shard id mappings. With this change, we notice the situation early, we halt when we would have to mint new ids in read-only mode. Which triggers a restart, at which point gen 2 probably sees the updated catalog state with shard id mappings.
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… read-only mode
Before, this scenario could happen when starting two deploy generations for the same environment concurrently:
materialize/src/storage-client/src/storage_collections.rs
Line 1384 in e3c1b3b
This isn't a correctness issue, the environment will hang forever or hit a timeout, halt, and restart, at which point it sees the catalog state with shard id mappings.
With this change, we notice the situation early, we halt when we would have to mint new ids in read-only mode. Which triggers a restart, at which point gen 2 probably sees the updated catalog state with shard id mappings.