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Christian Schwarz
035a49a6b2
(Found this useful during investigation https://github.com/neondatabase/cloud/issues/16886.) Problem ------- Before this PR, `neon_local` sequentially does the following: 1. launch storcon process 2. wait for storcon to signal readiness [here](https://github.com/neondatabase/neon/blob/75310fe441b87d399213e365f1364aa9f08aa40d/control_plane/src/storage_controller.rs#L804-L808) 3. start pageserver 4. wait for pageserver to become ready [here](https://github.com/neondatabase/neon/blob/c43e664ff577d4568722e4e7a2b2c6267b609607/control_plane/src/pageserver.rs#L343-L346) 5. etc The problem is that storcon's readiness waits for the [`startup_reconcile`](https://github.com/neondatabase/neon/blob/cbcd4058edb7a2c2bb3bfe1a6fc1ffb0d820b870/storage_controller/src/service.rs#L520-L523) to complete. But pageservers aren't started at this point. So, worst case we wait for `STARTUP_RECONCILE_TIMEOUT/2`, i.e., 15s. This is more than the 10s default timeout allowed by neon_local. So, the result is that `neon_local start` fails to start storcon and stops everything. Solution -------- In this PR I choose the the radical solution to start everything in parallel. It junks up the output because we do stuff like `print!(".")` to indicate progress. We should just abandon that. And switch to `utils::logging` + `tracing` with separate spans for each component. I can do that in this PR or we leave it as a follow-up. Alternatives Considered ----------------------- The Pageserver's `/v1/status` or in fact any endpoint of the mgmt API will not `accept()` on the mgmt API socket until after the `re-attach` call to storcon returned success. So, it's insufficient to change the startup order to start Pageservers first. We cannot easily change Pageserver startup order because `init_tenant_mgr` must complete before we start serving the mgmt API. Otherwise tenant detach calls et al can race with `init_tenant_mgr`. We'd have to add a "loading" state to tenant mgr and make all API endpoints except `/v1/status` wait for _that_ to complete. Related ------- - https://github.com/neondatabase/neon/pull/6475