## Problem
- Part of https://github.com/neondatabase/neon/issues/11113
- Building a new `reqwest::Client` for every request is expensive
because it parses CA certs under the hood. It's noticeable in storcon's
flamegraph.
## Summary of changes
- Reuse one `reqwest::Client` for all API calls to avoid parsing CA
certificates every time.
If a tenant gets deleted, delete also all of its timelines. We assume
that by the time a tenant is being deleted, no new timelines are being
created, so we don't need to worry about races with creation in this
situation.
Unlike #11233, which was very simple because it listed the timelines and
invoked timeline deletion, this PR obtains a list of safekeepers to
invoke the tenant deletion on, and then invokes tenant deletion on each
safekeeper that has one or multiple timelines.
Alternative to #11233
Builds on #11288
Part of #9011
There is no functional change here. We move safekeeper related code from
`service.rs` to `service/safekeeper_service.rs`, so that safekeeper
related stuff is contained in a single file. This also helps with
preventing `service.rs` from growing even further.
Part of #9011.
This PR extends the storcon with basic safekeeper management of
timelines, mainly timeline creation and deletion. We want to make the
storcon manage safekeepers in the future. Timeline creation is
controlled by the `--timelines-onto-safekeepers` flag.
1. it adds the `timelines` and `safekeeper_timeline_pending_ops` tables
to the storcon db
2. extend code for the timeline creation and deletion
4. it adds per-safekeeper reconciler tasks
TODO:
* maybe not immediately schedule reconciliations for deletions but have
a prior manual step
* tenant deletions
* add exclude API definitions (probably separate PR)
* how to choose safekeeper to do exclude on vs deletion? this can be a
bit hairy because the safekeeper might go offline in the meantime.
* error/failure case handling
* tests (cc test_explicit_timeline_creation from #11002)
* single safekeeper mode: we often only have one SK (in tests for
example)
* `notify-safekeepers` hook:
https://github.com/neondatabase/neon/issues/11163
TODOs implemented:
* cancellations of enqueued reconciliations on a per-timeline basis,
helpful if there is an ongoing deletion
* implement pending ops overwrite behavior
* load pending operations from db
RFC section for important reading:
[link](https://github.com/neondatabase/neon/blob/main/docs/rfcs/035-safekeeper-dynamic-membership-change.md#storage_controller-implementation)
Implements the bulk of #9011
Successor of #10440.
---------
Co-authored-by: Arseny Sher <sher-ars@yandex.ru>
## Problem
Somehow the previous patch loses the loop in the chaos injector function
so everything will only run once.
https://github.com/neondatabase/neon/pull/10934
## Summary of changes
Add back the loop.
Signed-off-by: Alex Chi Z <chi@neon.tech>
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
## Problem
close https://github.com/neondatabase/cloud/issues/24485
## Summary of changes
This patch adds a new chaos injection mode for the storcon. The chaos
injector reads the crontab and exits immediately at the configured time.
---------
Signed-off-by: Alex Chi Z <chi@neon.tech>
## Problem
Some situations may produce a large number of pending reconciles. If we
experience an issue where reconciles are processed more slowly than
expected, that can prevent us responding promptly to user requests like
tenant/timeline CRUD.
This is a cleaner implementation of the hotfix in
https://github.com/neondatabase/neon/pull/10815
## Summary of changes
- Introduce a second semaphore for high priority tasks, with
configurable units (default 256). The intent is that in practical
situations these user-facing requests should never have to wait.
- Use the high priority semaphore for: tenant/timeline CRUD, and shard
splitting operations. Use normal priority for everything else.
## Problem
In https://github.com/neondatabase/neon/pull/10438 it was pointed out
that it would be good to avoid picking tenants in ID order, and also to
avoid situations where we might double-select the same tenant.
There was an initial swing at this in
https://github.com/neondatabase/neon/pull/10443, where Chi suggested a
simpler approach which is done in this PR
## Summary of changes
- Split total set of tenants into in and out of home AZ
- Consume out of home AZ first, and if necessary shuffle + consume from
out of home AZ
## Problem
Since #9916 , the chaos code is actively fighting the optimizer: tenants
tend to be attached in their preferred AZ, so most chaos migrations were
moving them to a non-preferred AZ.
## Summary of changes
- When picking migrations, prefer to migrate things _toward_ their
preferred AZ when possible. Then pick shards to move the other way when
necessary.
The resulting behavior should be an alternating "back and forth" where
the chaos code migrates thiings away from home, and then migrates them
back on the next iteration.
The side effect will be that the chaos code actively helps to push
things into their home AZ. That's not contrary to its purpose though: we
mainly just want it to continuously migrate things to exercise
migration+notification code.
## Problem
We want to do a more robust job of scheduling tenants into their home
AZ: https://github.com/neondatabase/neon/issues/8264.
Closes: https://github.com/neondatabase/neon/issues/8969
## Summary of changes
### Scope
This PR combines prioritizing AZ with a larger rework of how we do
optimisation. The rationale is that just bumping AZ in the order of
Score attributes is a very tiny change: the interesting part is lining
up all the optimisation logic to respect this properly, which means
rewriting it to use the same scores as the scheduler, rather than the
fragile hand-crafted logic that we had before. Separating these changes
out is possible, but would involve doing two rounds of test updates
instead of one.
### Scheduling optimisation
`TenantShard`'s `optimize_attachment` and `optimize_secondary` methods
now both use the scheduler to pick a new "favourite" location. Then
there is some refined logic for whether + how to migrate to it:
- To decide if a new location is sufficiently "better", we generate
scores using some projected ScheduleContexts that exclude the shard
under consideration, so that we avoid migrating from a node with
AffinityScore(2) to a node with AffinityScore(1), only to migrate back
later.
- Score types get a `for_optimization` method so that when we compare
scores, we will only do an optimisation if the scores differ by their
highest-ranking attributes, not just because one pageserver is lower in
utilization. Eventually we _will_ want a mode that does this, but doing
it here would make scheduling logic unstable and harder to test, and to
do this correctly one needs to know the size of the tenant that one is
migrating.
- When we find a new attached location that we would like to move to, we
will create a new secondary location there, even if we already had one
on some other node. This handles the case where we have a home AZ A, and
want to migrate the attachment between pageservers in that AZ while
retaining a secondary location in some other AZ as well.
- A unit test is added for
https://github.com/neondatabase/neon/issues/8969, which is implicitly
fixed by reworking optimisation to use the same scheduling scores as
scheduling.
## Problem
When picking locations for a shard, we should use a ScheduleContext that
includes all the other shards in the tenant, so that we apply proper
anti-affinity between shards. If we don't do this, then it can lead to
unstable scheduling, where we place a shard somewhere that the optimizer
will then immediately move it away from.
We didn't always do this, because it was a bit awkward to accumulate the
context for a tenant rather than just walking tenants.
This was a TODO in `handle_node_availability_transition`:
```
// TODO: populate a ScheduleContext including all shards in the same tenant_id (only matters
// for tenants without secondary locations: if they have a secondary location, then this
// schedule() call is just promoting an existing secondary)
```
This is a precursor to https://github.com/neondatabase/neon/issues/8264,
where the current imperfect scheduling during node evacuation hampers
testing.
## Summary of changes
- Add an iterator type that yields each shard along with a
schedulecontext that includes all the other shards from the same tenant
- Use the iterator to replace hand-crafted logic in optimize_all_plan
(functionally identical)
- Use the iterator in `handle_node_availability_transition` to apply
proper anti-affinity during node evacuation.
## Problem
We may sometimes use scheduling modes like `Pause` to pin a tenant in
its current location for operational reasons. It is undesirable for the
chaos task to make any changes to such projects.
## Summary of changes
- Add a check for scheduling mode
- Add a log line when we do choose to do a chaos action for a tenant:
this will help us understand which operations originate from the chaos
task.
Chaos injection bridges the gap between automated testing (where we do
lots of different things with small, short-lived tenants), and staging
(where we do many fewer things, but with larger, long-lived tenants).
This PR adds a first type of chaos which isn't really very chaotic: it's
live migration of tenants between healthy pageservers. This nevertheless
provides continuous checks that things like clean, prompt shutdown of
tenants works for realistically deployed pageservers with realistically
large tenants.
