## Problem
gc-compaction needs the partitioning data to decide the job split. This
refactor allows concurrent access/computing the partitioning.
## Summary of changes
Make `partitioning` an ArcSwap so that others can access the
partitioning while we compute it. Fully eliminate the `repartition is
called concurrently` warning when gc-compaction is going on.
---------
Signed-off-by: Alex Chi Z <chi@neon.tech>
Rename the safekeeper scheduling policy "disabled" to "pause".
A rename was requested in
https://github.com/neondatabase/neon/pull/10400#discussion_r1916259124,
as the "disabled" policy is meant to be analogous to the "pause" policy
for pageservers.
Also simplify the `SkSchedulingPolicyArg::from_str` function, relying on
the `from_str` implementation of `SkSchedulingPolicy`. Latter is used
for the database format as well, so it is quite stable. If we ever want
to change the UI, we'll need to duplicate the function again but this is
cheap.
## Problem
Threads spawned in `test_tenant_delete_races_timeline_creation` are not
joined before the test ends, and can generate
`PytestUnhandledThreadExceptionWarning` in other tests.
https://neon-github-public-dev.s3.amazonaws.com/reports/pr-10419/12805365523/index.html#/testresult/53a72568acd04dbd
## Summary of changes
- Wrap threads in ThreadPoolExecutor which will join them before the
test ends
- Remove a spurious deletion call -- the background thread doing
deletion ought to succeed.
## Problem
When multiple changes are grouped in a merge group to be merged as part
of the merge queue, the changes might individually pass
`check-codestyle-rust` but not in their combined form.
## Summary of changes
- Move `check-codestyle-rust` into a reusable workflow that is called
from it's previous location in `build_and_test.yml`, and additionally
call it from `pre_merge_checks.yml`. The additional call does not run on
ARM, only x86, to ensure the merge queue continues being responsive.
- Trigger `pre_merge_checks.yml` on PRs that change any of the workflows
running in `pre_merge_checks.yml`, so that we get feedback on those
early an not only after trying to merge those changes.
This should fix the largest source of flakyness of
test_nbtree_pagesplit_cycleid.
## Problem
https://github.com/neondatabase/neon/issues/10390
## Summary of changes
By using a guaranteed-flushed LSN, we ensure that PS won't have to wait
forever.
(If it does wait forever, we know the issue can't be with Compute's WAL)
## Problem
As part of https://github.com/neondatabase/neon/issues/8614 we need to
pass options to START_WAL_PUSH.
## Summary of changes
Add two options. `allow_timeline_creation`, default true, disables
implicit timeline creation in the connection from compute. Eventually
such creation will be forbidden completely, but as we migrate to
configurations we need to support both: current mode and configurations
enabled where creation by compute is disabled.
`proto_version` specifies compute <-> sk protocol version. We have it
currently in the first greeting package also, but I plan to change tag
size from u64 to u8, which would make it hard to use. Command is more
appropriate place for it anyway.
This reduces pressure on the OS TCP read buffer by increasing the
moments we read data out of the receive buffer, and increasing the
number of bytes we can pull from that buffer when we do reads.
## Problem
A backend may not always consume its prefetch data quick enough
## Summary of changes
We add a new function `prefetch_pump_state` which pulls as many prefetch
requests from the OS TCP receive buffer as possible, but without
blocking.
This thus reduces pressure on OS-level TCP buffers, thus increasing
throughput by limiting throttling caused by full TCP buffers.
## Problem
part of https://github.com/neondatabase/neon/issues/9114
part of investigation of
https://github.com/neondatabase/neon/issues/10049
## Summary of changes
* If `cfg!(test) or cfg!(feature = testing)`, then we will always try
generating an image to ensure the history is replayable, but not put the
image layer into the final layer results, therefore discovering wrong
key history before we hit a read error.
* I suspect it's easier to trigger some races if gc-compaction is
continuously run on a timeline, so I increased the frequency to twice
per 10 churns.
* Also, create branches in gc-compaction smoke tests to get more test
coverage.
---------
Signed-off-by: Alex Chi Z <chi@neon.tech>
Co-authored-by: Arpad Müller <arpad@neon.tech>
## Problem
`postgres` is system database at neon, so we need to do `pg_restore`
into `neondb` instead
https://github.com/neondatabase/cloud/issues/22100
## Summary of changes
Changed fast_import a little bit:
1. After succesfull connection creating `neondb` in postgres instance
2. Changed restore connstring to use new db
3. Added optional `source_connection_string`, which allows to skip
`s3_prefix` and just connect directly.
4. Added `-i` that stops process until sigterm
## TODO
- [x] test image in cplane e2e
- [ ] Change import job image back to latest after this merged (partial
revert of https://github.com/neondatabase/cloud/pull/22338)
## Problem
When a pageserver is receiving high rates of requests, we don't have a
good way to efficiently discover what the client's access pattern is.
Closes: https://github.com/neondatabase/neon/issues/10275
## Summary of changes
- Add
`/v1/tenant/x/timeline/y/page_trace?size_limit_bytes=...&time_limit_secs=...`
API, which returns a binary buffer.
- Add `pagectl page-trace` tool to decode and analyze the output.
---------
Co-authored-by: Erik Grinaker <erik@neon.tech>
Implementing the last missing endpoint of #9981, this adds support to
set the scheduling policy of an individual safekeeper, as specified in
the RFC. However, unlike in the RFC we call the endpoint
`scheduling_policy` not `status`
Closes#9981.
As for why not use the upsert endpoint for this: we want to have the
safekeeper upsert endpoint be used for testing and for deploying new
safekeepers, but not for changes of the scheduling policy. We don't want
to change any of the other fields when marking a safekeeper as
decommissioned for example, so we'd have to first fetch them only to
then specify them again. Of course one can also design an endpoint where
one can omit any field and it doesn't get modified, but it's still not
great for observability to put everything into one big "change something
about this safekeeper" endpoint.
## Problem
Safekeepers currently decode and interpret WAL for each shard
separately.
This is wasteful in terms of CPU memory usage - we've seen this in
profiles.
## Summary of changes
Fan-out interpreted WAL to multiple shards.
The basic is that wal decoding and interpretation happens in a separate
tokio task and senders
attach to it. Senders only receive batches concerning their shard and
only past the Lsn they've last seen.
Fan-out is gated behind the `wal_reader_fanout` safekeeper flag
(disabled by default for now).
When fan-out is enabled, it might be desirable to control the absolute
delta between the
current position and a new shard's desired position (i.e. how far behind
or ahead a shard may be).
`max_delta_for_fanout` is a new optional safekeeper flag which dictates
whether to create a new
WAL reader or attach to the existing one. By default, this behaviour is
disabled. Let's consider enabling
it if we spot the need for it in the field.
## Testing
Tests passed [here](https://github.com/neondatabase/neon/pull/10301)
with wal reader fanout enabled
as of
34f6a71718.
Related: https://github.com/neondatabase/neon/issues/9337
Epic: https://github.com/neondatabase/neon/issues/9329
## Problem
https://github.com/neondatabase/neon/issues/9965
## Summary of changes
Add to safekeeper http endpoint to switch membership configuration. Also
add it to python client for tests, and add simple test itself.
## Problem
Successful `benchmarks` runs doesn't have enough visibility
Ref https://neondb.slack.com/archives/C069Z2199DL/p1736868055094539
## Summary of changes
- Report both successful and failed `benchmarks` to Slack
- Update `slackapi/slack-github-action` action
## Problem
Currently, we call `InterpretedWalRecord::from_bytes_filtered`
from each shard. To serve multiple shards at the same time,
the API needs to allow for enquiring about multiple shards.
## Summary of changes
This commit tweaks it a pretty brute force way. Naively, we could
just generate the shard for a key, but pre and post split shards
may be subscribed at the same time, so doing it efficiently is more
complex.
## Problem
https://github.com/neondatabase/neon/issues/9965
## Summary of changes
Add safekeeper membership configuration struct itself and storing it in
the control file. In passing also add creation timestamp to the control
file (there were cases where I wanted it in the past).
Remove obsolete unused PersistedPeerInfo struct from control file (still
keep it control_file_upgrade.rs to have it in old upgrade code).
Remove the binary representation of cfile in the roundtrip test.
Updating it is annoying, and we still test the actual roundtrip.
Also add configuration to timeline creation http request, currently used
only in one python test. In passing, slightly change LSNs meaning in the
request: normally start_lsn is passed (the same as ancestor_start_lsn in
similar pageserver call), but we allow specifying higher commit_lsn for
manual intervention if needed. Also when given LSN initialize
term_history with it.
## Problem
https://github.com/neondatabase/neon/pull/8455 wasn't specific enough on
migration from current situation to enabling generations.
## Summary of changes
Describe the missing parts, including control plane pushing generation
to compute, which also defines whether generations are enabled -- non
zero value does it.
## Problem
For large deployments, the `control/v1/tenant` listing API can time out
transmitting a monolithic serialized response.
## Summary of changes
- Add `limit` and `start_after` parameters to listing API
- Update storcon_cli to use these parameters and limit requests to 1000
items at a time
## Problem
With upload queue reordering in #10218, we can easily get into a
situation where multiple index uploads are queued back to back, which
can't be parallelized. This will happen e.g. when multiple layer flushes
enqueue layer/index/layer/index/... and the layers skip the queue and
are uploaded in parallel.
These index uploads will incur serial S3 roundtrip latencies, and may
block later operations.
Touches #10096.
## Summary of changes
When multiple back-to-back index uploads are ready to upload, only
upload the most recent index and drop the rest.
## Problem
The upload queue can currently schedule an arbitrary number of tasks.
This can both spawn an unbounded number of Tokio tasks, and also
significantly slow down upload queue scheduling as it's quadratic in
number of operations.
Touches #10096.
## Summary of changes
Limit the number of inprogress tasks to the remote storage upload
concurrency. While this concurrency limit is shared across all tenants,
there's certainly no point in scheduling more than this -- we could even
consider setting the limit lower, but don't for now to avoid
artificially constraining tenants.
By setting PATH in the 'pg-build' layer, all the extension build layers
will inherit. No need to pass PG_CONFIG to all the various make
invocations either: once pg_config is in PATH, the Makefiles will pick
it up from there.
## Problem
The upload queue currently sees significant head-of-line blocking. For
example, index uploads act as upload barriers, and for every layer flush
we schedule a layer and index upload, which effectively serializes layer
uploads.
Resolves#10096.
## Summary of changes
Allow upload queue operations to bypass the queue if they don't conflict
with preceding operations, increasing parallelism.
NB: the upload queue currently schedules an explicit barrier after every
layer flush as well (see #8550). This must be removed to enable
parallelism. This will require a better mechanism for compaction
backpressure, see e.g. #8390 or #5415.
## Problem
Since https://github.com/neondatabase/neon/pull/9916, the preferred AZ
of a tenant is much more impactful, and we would like to make it more
visible in tooling.
## Summary of changes
- Include AZ in node describe API
- Include AZ info in node & tenant outputs in CLI
- Add metrics for per-node shard counts, labelled by AZ
- Add a CLI for setting preferred AZ on a tenant
- Extend AZ-setting API+CLI to handle None for clearing preferred AZ
## Problem
Before this PR, the pagestream throttle was applied weighted on a
per-batch basis.
This had several problems:
1. The throttle occurence counters were only bumped by `1` instead of
`batch_size`.
2. The throttle wait time aggregator metric only counted one wait time,
irrespective
of `batch_size`. That makes sense in some ways of looking at it but not
in others.
3. If the last request in the batch runs into the throttle, the other
requests in the
batch are also throttled, i.e., over-throttling happens (theoretical,
didn't measure
it in practice).
## Solution
It occured to me that we can simply push the throttling upwards into
`pagestream_read_message`.
This has the added benefit that in pipeline mode, the `executor` stage
will, if it is idle,
steal whatever requests already made it into the `spsc_fold` and execute
them; before this
change, that was not the case - the throttling happened in the
`executor` stage instead of
the `batcher` stage.
## Code Changes
There are two changes in this PR:
1. Lifting up the throttling into the `pagestream_read_message` method.
2. Move the throttling metrics out of the `Throttle` type into
`SmgrOpMetrics`.
Unlike the other smgr metrics, throttling is per-tenant, hence the Arc.
3. Refactor the `SmgrOpTimer` implementation to account for the new
observation states,
and simplify its design.
4. Drive-by-fix flush time metrics. It was using the same `now` in the
`observe_guard` every time.
The `SmgrOpTimer` is now a state machine.
Each observation point moves the state machine forward.
If a timer object is dropped early some "pair"-like metrics still
require an increment or observation.
That's done in the Drop implementation, by driving the state machine to
completion.
## Problem
Discovered during the relation dir refactor work.
If we do not create images as in this patch, we would get two set of
image layers:
```
0000...METADATA_KEYS
0000...REL_KEYS
```
They overlap at the same LSN and would cause data loss for relation
keys. This doesn't happen in prod because initial image layer generation
is never called, but better to be fixed to avoid future issues with the
reldir refactors.
## Summary of changes
* Consolidate create_image_layers call into a single one.
---------
Signed-off-by: Alex Chi Z <chi@neon.tech>
## Problem
Because of https://github.com/Azure/azure-sdk-for-rust/issues/1739, our
identity token file was not being refreshed. This caused our uploads to
start failing when the storage token expired.
## Summary of changes
Drop and recreate the remote storage config every time we upload in
order to force reload the identity token file.
