NB: effectively a no-op in the neon env since the handling is config
gated
in storcon
## Problem
When a pageserver suffers from a local disk/node failure and restarts,
the storage controller will receive a re-attach call and return all the
tenants the pageserver is suppose to attach, but the pageserver will not
act on any tenants that it doesn't know about locally. As a result, the
pageserver will not rehydrate any tenants from remote storage if it
restarted following a local disk loss, while the storage controller
still thinks that the pageserver have all the tenants attached. This
leaves the system in a bad state, and the symptom is that PG's
pageserver connections will fail with "tenant not found" errors.
## Summary of changes
Made a slight change to the storage controller's `re_attach` API:
* The pageserver will set an additional bit `empty_local_disk` in the
reattach request, indicating whether it has started with an empty disk
or does not know about any tenants.
* Upon receiving the reattach request, if this `empty_local_disk` bit is
set, the storage controller will go ahead and clear all observed
locations referencing the pageserver. The reconciler will then discover
the discrepancy between the intended state and observed state of the
tenant and take care of the situation.
To facilitate rollouts this extra behavior in the `re_attach` API is
guarded by the `handle_ps_local_disk_loss` command line flag of the
storage controller.
---------
Co-authored-by: William Huang <william.huang@databricks.com>
## Problem
In #12217, we began passing the stripe size in reattach responses, and
persisting it in the on-disk state. This is necessary to ensure the
storage controller and Pageserver have a consistent view of the intended
stripe size of unsharded tenants, which will be used for splits that do
not specify a stripe size. However, for backwards compatibility, these
stripe sizes were optional.
## Summary of changes
Make the stripe sizes required for reattach responses and on-disk
location configs. These will always be provided by the previous
(current) release.
## Problem
The location config (which includes the stripe size) is stored on
pageserver disk.
For unsharded tenants we [do not include the shard identity in the
serialized
description](ad88ec9257/pageserver/src/tenant/config.rs (L64-L66)).
When the pageserver restarts, it reads that configuration and will use
the stripe size from there
and rely on storcon input from reattach for generation and mode.
The default deserialization is ShardIdentity::unsharded. This has the
new default stripe size of 2048.
Hence, for unsharded tenants we can be running with a stripe size
different from that the one in the
storcon observed state. This is not a problem until we shard split
without specifying a stripe size (i.e. manual splits via the UI or
storcon_cli). When that happens the new shards will use the 2048 stripe
size until storcon realises and switches them back. At that point it's
too late, since we've ingested data with the wrong stripe sizes.
## Summary of changes
Ideally, we would always have the full shard identity on disk. To
achieve this over two releases we do:
1. Always persist the shard identity in the location config on the PS.
2. Storage controller includes the stripe size to use in the re attach
response.
After the first release, we will start persisting correct stripe sizes
for any tenant shard that the storage controller
explicitly sends a location_conf. After the second release, the
re-attach change kicks in and we'll persist the
shard identity for all shards.
## Problem
Import up-calls did not enforce the usage of the latest generation. The
import might have finished in one previous generation, but not in the
latest one. Hence, the controller might try to activate a timeline
before it is ready. In theory, that would be fine, but it's tricky to
reason about.
## Summary of Changes
Pageserver provides the current generation in the upcall to the storage
controller and the later validates the generation. If the generation is
stale, we return an error which stops progress of the import job. Note
that the import job will retry the upcall until the stale location is
detached.
I'll add some proper tests for this as part of the [checkpointing
PR](https://github.com/neondatabase/neon/pull/11862).
Closes https://github.com/neondatabase/neon/issues/11884
## Problem
Pageservers notify control plane directly when a shard import has
completed.
Control plane has to download the status of each shard from S3 and
figure out if everything is truly done,
before proceeding with branch activation.
Issues with this approach are:
* We can't control shard split behaviour on the storage controller side.
It's unsafe to split
during import.
* Control plane needs to know about shards and implement logic to check
all timelines are indeed ready.
## Summary of changes
In short, storage controller coordinates imports, and, only when
everything is done, notifies control plane.
Big rocks:
1. Store timeline imports in the storage controller database. Each
import stores the status of its shards in the database.
We hook into the timeline creation call as our entry point for this.
2. Pageservers get a new upcall endpoint to notify the storage
controller of shard import updates.
3. Storage controller handles these updates by updating persisted state.
If an update finalizes the import,
then poll pageservers until timeline activation, and, then, notify the
control plane that the import is complete.
Cplane side change with new endpoint is in
https://github.com/neondatabase/cloud/pull/26166
Closes https://github.com/neondatabase/neon/issues/11566
## Problem
The pageserver upcall api was designed to work with control plane or the
storage controller.
We have completed the transition period and now the upcall api only
targets the storage controller.
## Summary of changes
Rename types accordingly and tweak some comments.
Updates storage components to edition 2024. We like to stay on the
latest edition if possible. There is no functional changes, however some
code changes had to be done to accommodate the edition's breaking
changes.
The PR has two commits:
* the first commit updates storage crates to edition 2024 and appeases
`cargo clippy` by changing code. i have accidentially ran the formatter
on some files that had other edits.
* the second commit performs a `cargo fmt`
I would recommend a closer review of the first commit and a less close
review of the second one (as it just runs `cargo fmt`).
part of https://github.com/neondatabase/neon/issues/10918
This change improves the resilience of the system to unclean restarts.
Previously, re-attach responses only included attached tenants
- If the pageserver had local state for a secondary location, it would
remain, but with no guarantee that it was still _meant_ to be there.
After this change, the pageserver will only retain secondary locations
if the /re-attach response indicates that they should still be there.
- If the pageserver had local state for an attached location that was
omitted from a re-attach response, it would be entirely detached. This
is wasteful in a typical HA setup, where an offline node's tenants might
have been re-attached elsewhere before it restarts, but the offline
node's location should revert to a secondary location rather than being
wiped. Including secondary tenants in the re-attach response enables the
pageserver to avoid throwing away local state unnecessarily.
In this PR:
- The re-attach items are extended with a 'mode' field.
- Storage controller populates 'mode'
- Pageserver interprets it (default is attached if missing) to construct
either a SecondaryTenant or a Tenant.
- A new test exercises both cases.
## Problem
Currently we manually register nodes with the storage controller, and
use a script during deploy to register with the cloud control plane.
Rather than extend that script further, nodes should just register on
startup.
## Summary of changes
- Extend the re-attach request to include an optional
NodeRegisterRequest
- If the `register` field is set, handle it like a normal node
registration before executing the normal re-attach work.
- Update tests/neon_local that used to rely on doing an explicit
register step that could be enabled/disabled.
---------
Co-authored-by: Christian Schwarz <christian@neon.tech>
## Problem
This is a precursor to adding a convenience CLI for the storage
controller.
## Summary of changes
- move controller api structs into pageserver_api::controller_api to
make them visible to other crates
- rename pageserver_api::control_api to pageserver_api::upcall_api to
match the /upcall/v1/ naming in the storage controller.
Why here rather than a totally separate crate? It's convenient to have
all the pageserver-related stuff in one place, and if we ever wanted to
move it to a different crate it's super easy to do that later.
