and add /metrics endpoint to compute_ctl to expose such metrics
metric format example for extension pg_rag
with versions 1.2.3 and 1.4.2
installed in 3 and 1 databases respectively:
neon_extensions_installed{extension="pg_rag", version="1.2.3"} = 3
neon_extensions_installed{extension="pg_rag", version="1.4.2"} = 1
------
infra part: https://github.com/neondatabase/flux-fleet/pull/251
---------
Co-authored-by: Tristan Partin <tristan@neon.tech>
## Problem
Followup to https://github.com/neondatabase/neon/pull/9677 which enables
`no_sync` in tests. This can be merged once the next release has
happened.
## Summary of changes
- Always run pageserver with `no_sync = true` in tests.
psycopg2 has the following warning related to autocommit:
> By default, any query execution, including a simple SELECT will start
> a transaction: for long-running programs, if no further action is
> taken, the session will remain “idle in transaction”, an undesirable
> condition for several reasons (locks are held by the session, tables
> bloat…). For long lived scripts, either ensure to terminate a
> transaction as soon as possible or use an autocommit connection.
In the 2.9 release notes, psycopg2 also made the following change:
> `with connection` starts a transaction on autocommit transactions too
Some of these connections are indeed long-lived, so we were retaining
tons of WAL on the endpoints because we had a transaction pinned in the
past.
Link: https://www.psycopg.org/docs/news.html#what-s-new-in-psycopg-2-9
Link: https://github.com/psycopg/psycopg2/issues/941
Signed-off-by: Tristan Partin <tristan@neon.tech>
Add a test that ensures the `retain_lsn` functionality works. Right now,
there is not a single test that is broken if offloaded or non-offloaded
timelines don't get registered at their parents, preventing gc from
discarding the ancestor_lsns of the children. This PR fills that gap.
The test has four modes:
* `offloaded`: offload the child timeline, run compaction on the parent
timeline, unarchive the child timeline, then try reading from it.
hopefully the data is still there.
* `offloaded-corrupted`: offload the child timeline, corrupts the
manifest in a way that the pageserver believes the timeline was
flattened. This is the closest we can get to pretend the `retain_lsn`
mechanism doesn't exist for offloaded timelines, so we can avoid adding
endpoints to the pageserver that do this manually for tests. The test
then checks that indeed data is corrupted and the endpoint can't be
started. That way we know that the test is actually working, and
actually tests the `retain_lsn` mechanism, instead of say the lsn lease
mechanism, or one of the many other mechanisms that impede gc.
* `archived`: the child timeline gets archived but doesn't get
offloaded. this currently matches the `None` case but we might have
refactors in the future that make archived timelines sufficiently
different from non-archived ones.
* `None`: the child timeline doesn't even get archived. this tests that
normal timelines participate in `retain_lsn`. I've made them locally not
participate in `retain_lsn` (via commenting out the respective
`ancestor_children.push` statement in tenant.rs) and ran the testsuite,
and not a single test failed. So this test is first of its kind.
Part of #8088.
## Problem
Running `pytest.skip(...)` in a test body instead of marking the test
with `@pytest.mark.skipif(...)` makes all fixtures to be initialised,
which is not necessary if the test is going to be skipped anyway.
Also, some tests are unnecessarily skipped (e.g. `test_layer_bloating`
on Postgres 17, or `test_idle_reconnections` at all) or run (e.g.
`test_parse_project_git_version_output_positive` more than on once
configuration) according to comments.
## Summary of changes
- Move `skip_on_postgres` / `xfail_on_postgres` /
`run_only_on_default_postgres` decorators to `fixture.utils`
- Add new `skip_in_debug_build` and `skip_on_ci` decorators
- Replace `pytest.skip(...)` calls with decorators where possible
Perf benchmarks produce a lot of layers.
## Summary of changes
Bumping the threshold and ignore the warning.
---------
Signed-off-by: Alex Chi Z <chi@neon.tech>
Right now, our environments create databases with the C locale, which is
really unfortunate for users who have data stored in other languages
that they want to analyze. For instance, show_trgm on Hebrew text
currently doesn't work in staging or production.
I don't envision this being the final solution. I think this is just a
way to set a known value so the pageserver doesn't use its parent
environment. The final solution to me is exposing initdb parameters to
users in the console. Then they could use a different locale or encoding
if they so chose.
Signed-off-by: Tristan Partin <tristan@neon.tech>
## Problem
Replication slots are now persisted using AUX files mechanism and
included in basebackup when replica is launched.
This slots are not somehow used at replica but hold WAL, which may cause
local disk space exhaustion.
## Summary of changes
Add `--replica` parameter to basebackup request and do not include
replication slot state files in basebackup for replica.
## Checklist before requesting a review
- [ ] I have performed a self-review of my code.
- [ ] If it is a core feature, I have added thorough tests.
- [ ] Do we need to implement analytics? if so did you add the relevant
metrics to the dashboard?
- [ ] If this PR requires public announcement, mark it with
/release-notes label and add several sentences in this section.
## Checklist before merging
- [ ] Do not forget to reformat commit message to not include the above
checklist
---------
Co-authored-by: Konstantin Knizhnik <knizhnik@neon.tech>
## Problem
When we create a new segment, we zero it out in order to avoid changing
the length and fsyncing metadata on every write. However, we zeroed it
out by writing 8 KB zero-pages, and Tokio file writes have non-trivial
overhead.
## Summary of changes
Zero out the segment using
[`File::set_len()`](https://docs.rs/tokio/latest/i686-unknown-linux-gnu/tokio/fs/struct.File.html#method.set_len)
instead. This will typically (depending on the filesystem) just write a
sparse file and omit the 16 MB of data entirely. This improves WAL
append throughput for large messages by over 400% with fsync disabled,
and 100% with fsync enabled.
Fix direct reading from WAL buffers.
Pointer wasn't advanced which resulted in sending corrupted WAL if part
of read used WAL buffers and part read from the file. Also move it to
neon_walreader so that e.g. replication could also make use of it.
ref https://github.com/neondatabase/cloud/issues/19567
We need to use the shard associated with the layer file, not the shard
associated with our current tenant shard ID.
Due to shard splits, the shard IDs can refer to older files.
close https://github.com/neondatabase/neon/issues/9667
Fixes#9518.
## Problem
After removing the assertion `layers_removed == 0` in #9506, we could
miss breakage if we solely rely on the successful execution of the
`SELECT` query to check if lease is properly protecting layers. Details
listed in #9518.
Also, in integration tests, we sometimes run into the race condition
where getpage request comes before the lease get renewed (item 2 of
#8817), even if compute_ctl sends a lease renewal as soon as it sees a
`/configure` API calls that updates the `pageserver_connstr`. In this
case, we would observe a getpage request error stating that we `tried to
request a page version that was garbage collected` (as we seen in
[Allure
Report](https://neon-github-public-dev.s3.amazonaws.com/reports/pr-8613/11550393107/index.html#suites/3ccffb1d100105b98aed3dc19b717917/d1a1ba47bc180493)).
## Summary of changes
- Use layer map dump to verify if the lease protects what it claimed:
Record all historical layers that has `start_lsn <= lease_lsn` before
and after running timeline gc. This is the same check as
ad79f42460/pageserver/src/tenant/timeline.rs (L5025-L5027)
The set recorded after GC should contain every layer in the set recorded
before GC.
- Wait until log contains another successful lease request before
running the `SELECT` query after GC. We argued in #8817 that the bad
request can only exist within a short period after migration/restart,
and our test shows that as long as a lease renewal is done before the
first getpage request sent after reconfiguration, we will not have bad
request.
Signed-off-by: Yuchen Liang <yuchen@neon.tech>
Problem
-------
Tests that directly call the Pageserver Management API to set tenant
config are flaky if the Pageserver is managed by Storcon because Storcon
is the source of truth and may (theoretically) reconcile a tenant at any
time.
Solution
--------
Switch all users of
`set_tenant_config`/`patch_tenant_config_client_side`
to use the `env.storage_controller.pageserver_api()`
Future Work
-----------
Prevent regressions from creeping in.
And generally clean up up tenant configuration.
Maybe we can avoid the Pageserver having a default tenant config at all
and put the default into Storcon instead?
* => https://github.com/neondatabase/neon/issues/9621
Refs
----
fixes https://github.com/neondatabase/neon/issues/9522
Adds a Python benchmark for sharded ingestion. This ingests 7 GB of WAL
(100M rows) into a Safekeeper and fans out to 10 shards running on 10
different pageservers. The ingest volume and duration is recorded.
## Problem
`tenant_get_shards()` does not work with a sharded tenant on 1
pageserver, as it assumes an unsharded tenant in this case. This special
case appears to have been added to handle e.g. `test_emergency_mode`,
where the storage controller is stopped. This breaks e.g. the sharded
ingest benchmark in #9591 when run with a single shard.
## Summary of changes
Correctly look up shards even with a single pageserver, but add a
special case that assumes an unsharded tenant if the storage controller
is stopped and the caller provides an explicit pageserver, in order to
accomodate `test_emergency_mode`.
## Problem
The final part of https://github.com/neondatabase/neon/issues/9543 will
be a chaos test that creates/deletes/archives/offloads timelines while
restarting pageservers and migrating tenants. Developing that test
showed up a few places where we log errors during normal shutdown.
## Summary of changes
- UninitializedTimeline's drop should log at info severity: this is a
normal code path when some part of timeline creation encounters a
cancellation `?` path.
- When offloading and finding a `RemoteTimelineClient` in a
non-initialized state, this is not an error and should not be logged as
such.
- The `offload_timeline` function returned an anyhow error, so callers
couldn't gracefully pick out cancellation errors from real errors:
update this to have a structured error type and use it throughout.
If we delete a timeline that has childen, those children will have their
data corrupted. Therefore, extend the already existing safety check to
offloaded timelines as well.
Part of #8088
Disallow a request for timeline ancestor detach if either the to be
detached timeline, or any of the to be reparented timelines are
offloaded or archived.
In theory we could support timelines that are archived but not
offloaded, but archived timelines are at the risk of being offloaded, so
we treat them like offloaded timelines. As for offloaded timelines, any
code to "support" them would amount to unoffloading them, at which point
we can just demand to have the timelines be unarchived.
Part of #8088
python based regression test setup for auth_broker. This uses a http
mock for cplane as well as the JWKs url.
complications:
1. We cannot just use local_proxy binary, as that requires the
pg_session_jwt extension which we don't have available in the current
test suite
2. We cannot use just any old http mock for local_proxy, as auth_broker
requires http2 to local_proxy
as such, I used the h2 library to implement an echo server - copied from
the examples in the h2 docs.
As pointed out in
https://github.com/neondatabase/neon/pull/9489#discussion_r1814699683 ,
we currently didn't support deletion for offloaded timelines after the
timeline has been loaded from the manifest instead of having been
offloaded.
This was because the upload queue hasn't been initialized yet. This PR
thus initializes the timeline and shuts it down immediately.
Part of #8088
We will only have a C string if the specified role is a string.
Otherwise, we need to resolve references to public, current_role,
current_user, and session_user.
Fixes: https://github.com/neondatabase/cloud/issues/19323
Signed-off-by: Tristan Partin <tristan@neon.tech>
As a DBaaS provider, Neon needs to provide a stable platform for
customers to build applications upon. At the same time however, we also
need to enable customers to use the latest and greatest technology, so
they can prototype their work, and we can solicit feedback. If all
extensions are treated the same in terms of stability, it is hard to
meet that goal.
There are now two new GUCs created by the Neon extension:
neon.allow_unstable_extensions: This is a session GUC which allows
a session to install and load unstable extensions.
neon.unstable_extensions: This is a comma-separated list of extension
names. We can check if a CREATE EXTENSION statement is attempting to
install an unstable extension, and if so, deny the request if
neon.allow_unstable_extensions is not set to true.
Signed-off-by: Tristan Partin <tristan@neon.tech>
Co-authored-by: Konstantin Knizhnik <knizhnik@neon.tech>
## Problem
Part of https://github.com/neondatabase/neon/issues/8623
## Summary of changes
Removed all aux-v1 config processing code. Note that we persisted it
into the index part file, so we cannot really remove the field from
index part. I also kept the config item within the tenant config, but we
will not read it any more.
---------
Signed-off-by: Alex Chi Z <chi@neon.tech>
## Problem
We haven't historically taken this API route where we would onboard a
tenant to the controller in detached state. It worked, but we didn't
have test coverage.
## Summary of changes
- Add a test that onboards a tenant to the storage controller in
Detached mode, and checks that deleting it without attaching it works as
expected.
## Problem
If something goes wrong with a live migration, we currently only have
awkward ways to interrupt that:
- Restart the storage controller
- Ask it to do some other modification/migration on the shard, which we
don't really want.
## Summary of changes
- Add a new `/cancel` control API, and storcon_cli wrapper for it, which
fires the Reconciler's cancellation token. This is just for on-call use
and we do not expect it to be used by any other services.
## Problem
When we use pull_timeline API on an evicted timeline, it gets downloaded
to serve the snapshot API request. That means that to evacuate all the
timelines from a node, the node needs enough disk space to download
partial segments from all timelines, which may not be physically the
case.
Closes: #8833
## Summary of changes
- Add a "try" variant of acquiring a residence guard, that returns None
if the timeline is offloaded
- During snapshot API handler, take a different code path if the
timeline isn't resident, where we just read the checkpoint and don't try
to read any segments.
In complement to
https://github.com/neondatabase/tokio-epoll-uring/pull/56.
## Problem
We want to make tokio-epoll-uring slots waiters queue depth observable
via Prometheus.
## Summary of changes
- Add `pageserver_tokio_epoll_uring_slots_submission_queue_depth`
metrics as a `Histogram`.
- Each thread-local tokio-epoll-uring system is given a `LocalHistogram`
to observe the metrics.
- Keep a list of `Arc<ThreadLocalMetrics>` used on-demand to flush data
to the shared histogram.
- Extend `Collector::collect` to report
`pageserver_tokio_epoll_uring_slots_submission_queue_depth`.
Signed-off-by: Yuchen Liang <yuchen@neon.tech>
Co-authored-by: Christian Schwarz <christian@neon.tech>
## Problem
We have some known N^2 behaviors when it comes to large relation counts,
due to the monolithic encoding and full rewrites of of RelDirectory each
time a relation is added. Ordinarily our backpressure mechanisms give
"slow but steady" performance when creating/dropping/truncating
relations. However, in the case of a transaction abort, it is possible
for a single WAL record to drop an unbounded number of relations. The
results in an unavailable compute, as when it sends one of these
records, it can stall the pageserver's ingest for many minutes, even
though the compute only sent a small amount of WAL.
Closes https://github.com/neondatabase/neon/issues/9505
## Summary of changes
- Rewrite relation-dropping code to do one read/modify/write cycle of
RelDirectory, instead of doing it separately for each relation in a
loop.
- Add a test for the bug scenario encountered:
`test_tx_abort_with_many_relations`
The test has ~40s runtime on my workstation. About 1 second of that is
the part where we wait for ingest to catch up after a rollback, the rest
is the slowness of creating and truncating a large number of relations.
---------
Co-authored-by: Heikki Linnakangas <heikki@neon.tech>
Previously it inserted ~150MiB of WAL while expecting page fetching to
work in 1s (wait_lsn_timeout=1s). It failed in CI in debug builds.
Instead, just directly wait for the wanted condition, i.e. needed
safekeepers are reported in pageserver timed out waiting for WAL error
message. Also set NEON_COMPUTE_TESTING_BASEBACKUP_RETRIES to 1 in this
test and neighbour one, it reduces execution time from 2.5m to ~10s.
This PR adds a pageserver mgmt API to scan a layer file for disposable
keys.
It hooks it up to the sharding compaction test, demonstrating that we're
not filtering out all disposable keys.
This is extracted from PGDATA import
(https://github.com/neondatabase/neon/pull/9218)
where I do the filtering of layer files based on `is_key_disposable`.
Fixes#9098
## Problem
`test_readonly_node_gc` is flaky. As shown in [Allure
Report](https://neon-github-public-dev.s3.amazonaws.com/reports/pr-9469/11444519440/index.html#suites/3ccffb1d100105b98aed3dc19b717917/2c02073738fa2b39),
we would get a `AssertionError: No layers should be removed, old layers
are guarded by leases.` after the test restarts pageservers or after
reconfigure pageservers.
During the investigation, we found that the layers has LSN (`0/1563088`)
greater than the LSN (`0x1562000`) protected by the lease. For instance,
**Layers removed**
<pre>
000000067F00000005000034540100000000-000000067F00000005000040050100000000__000000000<b><i>1563088</i></b>-00000001
(shard 0002)
000000068000000000000017E20000000001-010000000100000001000000000000000001__000000000<b><i>1563088</i></b>-00000001
(shard 0002)
</pre>
**Lsn Lease Granted**
<pre>
handle_make_lsn_lease{lsn=<b><i>0/1562000</i></b> shard_id=0002
shard_id=0002}: lease created, valid until 2024-10-21
</pre>
This means that these layers are not guarded by the leases: they are in
"future", not visible to the static endpoint.
## Summary of changes
- Remove the assertion layers_removed == 0 after trigger timeline GC
while holding the lease. Instead rely on the successful execution of
the`SELECT` query to test lease validity.
- Improve test logging
Signed-off-by: Yuchen Liang <yuchen@neon.tech>
Before, we didn't copy over the `index-part.json` of offloaded timelines
to the new shard's location, resulting in the new shard not knowing the
timeline even exists.
In #9444, we copy over the manifest, but we also need to do this for
`index-part.json`.
As the operations to do are mostly the same between offloaded and
non-offloaded timelines, we can iterate over all of them in the same
loop, after the introduction of a `TimelineOrOffloadedArcRef` type to
generalize over the two cases. This is analogous to the deletion code
added in #8907.
The added test also ensures that the sharded archival config endpoint
works, something that has not yet been ensured by tests.
Part of #8088
# Problem
Timeline creation can either be bootstrap or branch.
The distinction is made based on whether the `ancestor_*` fields are
present or not.
In the PGDATA import code
(https://github.com/neondatabase/neon/pull/9218), I add a third variant
to timeline creation.
# Solution
The above pushed me to refactor the code in Pageserver to distinguish
the different creation requests through enum variants.
There is no externally observable effect from this change.
On the implementation level, a notable change is that the acquisition of
the `TimelineCreationGuard` happens later than before. This is necessary
so that we have everything in place to construct the
`CreateTimelineIdempotency`. Notably, this moves the acquisition of the
creation guard _after_ the acquisition of the `gc_cs` lock in the case
of branching. This might appear as if we're at risk of holding `gc_cs`
longer than before this PR, but, even before this PR, we were holding
`gc_cs` until after the `wait_completion()` that makes the timeline
creation durable in S3 returns. I don't see any deadlock risk with
reversing the lock acquisition order.
As a drive-by change, I found that the `create_timeline()` function in
`neon_local` is unused, so I removed it.
# Refs
* platform context: https://github.com/neondatabase/neon/pull/9218
* product context: https://github.com/neondatabase/cloud/issues/17507
* next PR stacked atop this one:
https://github.com/neondatabase/neon/pull/9501
## Problem
WAL ingest couples decoding of special records with their handling
(updates to the storage engine mostly).
This is a roadblock for our plan to move WAL filtering (and implicitly
decoding) to safekeepers since they cannot
do writes to the storage engine.
## Summary of changes
This PR decouples the decoding of the special WAL records from their
application. The changes are done in place
and I've done my best to refrain from refactorings and attempted to
preserve the original code as much as possible.
Related: https://github.com/neondatabase/neon/issues/9335
Epic: https://github.com/neondatabase/neon/issues/9329
Persist timeline offloaded state to S3.
Right now, as of #8907, at each restart of the pageserver, all offloaded
state is lost, so we load the full timeline again. As it starts with an
empty local directory, we might potentially download some files again,
leading to downloads that are ultimately wasteful.
This patch adds support for persisting the offloaded state, allowing us
to never load offloaded timelines in the first place. The persistence
feature is facilitated via a new file in S3 that is tenant-global, which
contains a list of all offloaded timelines. It is updated each time we
offload or unoffload a timeline, and otherwise never touched.
This choice means that tenants where no offloading is happening will not
immediately get a manifest, keeping the change very minimal at the
start.
We leave generation support for future work. It is important to support
generations, as in the worst case, the manifest might be overwritten by
an older generation after a timeline has been unoffloaded (and
unarchived), so the next pageserver process instantiation might wrongly
believe that some timeline is still offloaded even though it should be
active.
Part of #9386, #8088
## Problem
If the environment variables `COMPATIBILITY_NEON_BIN` or
`COMPATIBILITY_POSTGRES_DISTRIB_DIR` are not set (this is usual during a
local run), the tests with the versions mix cannot run.
## Summary of changes
If these variables are not set turn off the version mix.
---------
Co-authored-by: Alexander Bayandin <alexander@neon.tech>
## Problem
Previously, figuring out how many tenant shards were managed by a
storage controller was typically done by peeking at the database or
calling into the API. A metric makes it easier to monitor, as
unexpectedly increasing shard counts can be indicative of problems
elsewhere in the system.
## Summary of changes
- Add metrics `storage_controller_pageserver_nodes` (updated on node
CRUD operations from Service) and `storage_controller_tenant_shards`
(updated RAII-style from TenantShard)
Adds endpoint to install extensions:
**POST** `/extensions`
```
{"extension":"pg_sessions_jwt","database":"neondb","version":"1.0.0"}
```
Will be used by `local-proxy`.
Example, for the JWT authentication to work the database needs to have
the pg_session_jwt extension and also to enable JWT to work in RLS
policies.
---------
Co-authored-by: Conrad Ludgate <conradludgate@gmail.com>
