This PR adds a plugin that automatically reruns (up to 3 times) flaky
tests. Internally, it uses data from `TEST_RESULT_CONNSTR` database and
`pytest-rerunfailures` plugin.
As the first approximation we consider the test flaky if it has failed on
the main branch in the last 10 days.
Flaky tests are fetched by `scripts/flaky_tests.py` script (it's
possible to use it in a standalone mode to learn which tests are flaky),
stored to a JSON file, and then the file is passed to the pytest plugin.
This patch adds a pageserver-global background loop that evicts layers
in response to a shortage of available bytes in the $repo/tenants
directory's filesystem.
The loop runs periodically at a configurable `period`.
Each loop iteration uses `statvfs` to determine filesystem-level space
usage. It compares the returned usage data against two different types
of thresholds. The iteration tries to evict layers until app-internal
accounting says we should be below the thresholds. We cross-check this
internal accounting with the real world by making another `statvfs` at
the end of the iteration. We're good if that second statvfs shows that
we're _actually_ below the configured thresholds. If we're still above
one or more thresholds, we emit a warning log message, leaving it to the
operator to investigate further.
There are two thresholds:
- `max_usage_pct` is the relative available space, expressed in percent
of the total filesystem space. If the actual usage is higher, the
threshold is exceeded.
- `min_avail_bytes` is the absolute available space in bytes. If the
actual usage is lower, the threshold is exceeded.
The iteration evicts layers in LRU fashion with a reservation of up to
`tenant_min_resident_size` bytes of the most recent layers per tenant.
The layers not part of the per-tenant reservation are evicted
least-recently-used first until we're below all thresholds. The
`tenant_min_resident_size` can be overridden per tenant as
`min_resident_size_override` (bytes).
In addition to the loop, there is also an HTTP endpoint to perform one
loop iteration synchronous to the request. The endpoint takes an
absolute number of bytes that the iteration needs to evict before
pressure is relieved. The tests use this endpoint, which is a great
simplification over setting up loopback-mounts in the tests, which would
be required to test the statvfs part of the implementation. We will rely
on manual testing in staging to test the statvfs parts.
The HTTP endpoint is also handy in emergencies where an operator wants
the pageserver to evict a given amount of space _now. Hence, it's
arguments documented in openapi_spec.yml. The response type isn't
documented though because we don't consider it stable. The endpoint
should _not_ be used by Console but it could be used by on-call.
Co-authored-by: Joonas Koivunen <joonas@neon.tech>
Co-authored-by: Dmitry Rodionov <dmitry@neon.tech>
Co-authored-by: Heikki Linnakangas <heikki@neon.tech>
## Describe your changes
Added a query param to detach API
Allow to remove local state of a tenant even if its not in the memory
(following ignore API)
## Issue ticket number and link
#3828
## Checklist before requesting a review
- [x] 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.
---------
Co-authored-by: Kirill Bulatov <kirill@neon.tech>
The PR enforces current newest `index_part.json` format in the type
system (version `1`), not allowing any previous forms of it, that were
used in the past.
Similarly, the code to mitigate the
https://github.com/neondatabase/neon/issues/3024 issue is now also
removed.
Current code does not produce old formats and extra files in the
index_part.json, in the future we will be able to use
https://github.com/neondatabase/aversion or other approach to make
version transitions more explicit.
See https://neondb.slack.com/archives/C033RQ5SPDH/p1679134185248119 for
the justification on the breaking changes.
This patch adds two metrics that will enable us to detect *thrashing* of
layers, i.e., repetitions of `eviction, on-demand-download, eviction,
... ` for a given layer.
The first metric counts all layer evictions per timeline. It requires no
further explanation. The second metric counts the layer evictions where
the layer was resident for less than a given threshold.
We can alert on increments to the second metric. The first metric will
serve as a baseline, and further, it's generally interesting, outside of
thrashing.
The second metric's threshold is configurable in PageServerConf and
defaults to 24h. The threshold value is reproduced as a label in the
metric because the counter's value is semantically tied to that
threshold. Since changes to the config and hence the label value are
infrequent, this will have low storage overhead in the metrics storage.
The data source to determine the time that the layer was resident is the
file's `mtime`. Using `mtime` is more of a crutch. It would be better if
Pageserver did its own persistent bookkeeping of residence change events
instead of relying on the filesystem. We had some discussion about this:
https://github.com/neondatabase/neon/pull/3809#issuecomment-1470448900
My position is that `mtime` is good enough for now. It can theoretically
jump forward if someone copies files without resetting `mtime`. But that
shouldn't happen in practice. Note that moving files back and forth
doesn't change `mtime`, nor does `chown` or `chmod`. Lastly, `rsync -a`,
which is typically used for filesystem-level backup / restore, correctly
syncs `mtime`.
I've added a label that identifies the data source to keep options open
for a future, better data source than `mtime`. Since this value will
stay the same for the time being, it's not a problem for metrics
storage.
refs https://github.com/neondatabase/neon/issues/3728
The control plane currently only supports EdDSA. We need to either teach
the storage to use EdDSA, or the control plane to use RSA. EdDSA is more
modern, so let's use that.
We could support both, but it would require a little more code and tests,
and we don't really need the flexibility since we control both sides.
This allows you to run without the 'openssl' binary as long as you
don't enable authentication. This becomes more important with the next
commit, which switches the JWT algorithm to EdDSA. LibreSSL does not
support EdDSA, and LibreSSL comes with macOS, so the next commit makes
it much more likely for the key generation to fail for macOS users.
To allow running without a keypair, don't generate the authentication
token in the 'neon_local init' step. Instead, generate a new token on
every request that needs one, using the private key.
## Describe your changes
Add Error enum for tenant state response to allow better error handling
in mgmt api
## Issue ticket number and link
#2238
## Checklist before requesting a review
- [x] 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.
Create `safekeeper_pg_io_bytes_total` metric to track total amount of
bytes written/read in a postgres connections to safekeepers. This metric
has the following labels:
- `client_az` – availability zone of the connection initiator, or
`"unknown"`
- `sk_az` – availability zone of the safekeeper, or `"unknown"`
- `app_name` – `application_name` of the postgres client
- `dir` – data direction, either `"read"` or `"write"`
- `same_az` – `"true"`, `"false"` or `"unknown"`. Can be derived from
`client_az` and `sk_az`, exists purely for convenience.
This is implemented by passing availability zone in the connection
string, like this: `-c tenant_id=AAA timeline_id=BBB
availability-zone=AZ-1`.
Update ansible deployment scripts to add availability_zone argument
to safekeeper and pageserver in systemd service files.
this failure case was probably introduced by b220ba6, because earlier
the gc would always have run fast enough for restart every 1s. however,
test got added later, so we have just been lucky.
fixes#3824 by allowing this error to happen.
This makes it possible to enable authentication only for the mgmt HTTP
API or the compute API. The HTTP API doesn't need to be directly
accessible from compute nodes, and it can be secured through network
policies. This also allows rolling out authentication in a piecemeal
fashion.
There was a warning for trailing garbage after end-of-tar archive, but
it didn't always work. The reason is that we created a StreamReader
over the original copyin-stream, but performed the check for garbage
on the copyin-stream. There could be some garbage bytes buffered in
the StreamReader, which were not caught by the warning.
I considered turning the the warning into a fatal error, aborting the
import, but I wasn't sure if we handle aborting the import properly.
Do we clean up the timeline directory on error? If we don't, we should
make that more robust, but that's a different story.
Also, normally a valid tar archive ends with two 512-byte blocks of zeros.
The tokio_tar crate stops at the first all-zeros block. Read and check
the second all-zeros block, and error out if it's not there, or contains
something unexpected.
Adds two new *global* metrics:
- pageserver_remote_ondemand_downloaded_layers_total
- pageserver_remote_ondemand_downloaded_bytes_total
An existing test is repurposed once more to check that we do get some
reasonable counts. These are to replace guessing from the nic RX bytes
metric how much was on-demand downloaded.
First part of #3745: This does not add the "(un)?avoidable" metric,
which I plan to add as a new metric, which will be a subset of the
counts of the metrics added here.
…start transparent for clients
## Describe your changes
Try to reestablish connection with pageserver if send is failed to be
able to make pageserver restart transparent for client
## Issue ticket number and link
https://github.com/neondatabase/neon/issues/1138
## 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.
---------
Co-authored-by: Heikki Linnakangas <heikki@neon.tech>
- Add support for splitting async postgres_backend into read and write halfes.
Safekeeper needs this for bidirectional streams. To this end, encapsulate
reading-writing postgres messages to framed.rs with split support without any
additional changes (relying on BufRead for reading and BytesMut out buffer for
writing).
- Use async postgres_backend throughout safekeeper (and in proxy auth link
part).
- In both safekeeper COPY streams, do read-write from the same thread/task with
select! for easier error handling.
- Tidy up finishing CopyBoth streams in safekeeper sending and receiving WAL
-- join split parts back catching errors from them before returning.
Initially I hoped to do that read-write without split at all, through polling
IO:
https://github.com/neondatabase/neon/pull/3522
However that turned out to be more complicated than I initially expected
due to 1) borrow checking and 2) anon Future types. 1) required Rc<Refcell<...>>
which is Send construct just to satisfy the checker; 2) can be workaround with
transmute. But this is so messy that I decided to leave split.
We have a few tests that try to set image_creation_threshold, but it
didn't actually have any effect because we were missing some critical
code to load the setting from config file into memory.
The two modified tests in `test_remote_storage.py perform
compaction and GC, and assert that GC removes some layers. That
only happens if new image layers are created by the
compaction. The tests explicitly disabled image layer creation by
setting image_creation_threshold to a high value, but it didn't
take effect because reading image_creation_threshold from config
file was broken, which is why the test worked. Fix the test to
set image_creation_threshold low, instead, so that GC has work to
do.
Change 'test_tenant_conf.py' so that it exercises the added code.
This might explain why we're apparently missing test coverage for GC
(issue #3415), although I didn't try to address that here, nor did I
check if this improves the it.
* Stop allocating and maintaining 128MB hash table for last written
LSN cache as it is not needed in wal-redo.
* Do not require access to the initialized data directory. That
saves few dozens megabytes of empty but initialized data directory.
Currently such directories do occupy about 10% of the disk space
on the pageservers as most of tenants are empty.
* Move shmem-initialization code to the extension instead of postgres
The test already allows the background thread trying to checkpoint to
fail, however the resulting log message is currently not allowed thus
causing flakyness.
Commit
0cf7fd0fb8
Compaction with on-demand download (#3598)
introduced a subtle bug: if we don't have to do on-demand downloads,
we only take one ROUND in fn compact() and exit early.
Thereby, we miss scheduling the index part upload for any layers
created by fn compact_inner().
Before that commit, we didn't have this problem.
So, this patch fixes it.
Since no regression test caught this, I went ahead and extended the
timeline size tests to assert that, if remote storage is configured,
1. pageserver_remote_physical_size matches the other physical sizes
2. file sizes reported by the layer map info endpoint match the other
physical size metrics
Without the pageserver code fix, the regression test would
fail at the physical size assertion, complaining that
any of the resident physical size != remote physical size metric
50790400.0 != 18399232.0
I figured out what the problem is by comparing the remote storage
and local directories like so, and noticed that the image layer
in the local directory wasn't present on the remote side.
It's size was exactly the difference
50790400.0 - 18399232.0 =32391168.0
fixes https://github.com/neondatabase/neon/issues/3738
- use parse_metrics() in all places where we parse Prometheus metrics
- query_all: make `filter` argument optional
- encourage using properly parsed, typed metrics by changing get_metrics()
to return already-parsed metrics. The new get_metric_str() method,
like in the Safekeeper type, returns the raw text response.
Before this patch, GC would call PersistentLayer::delete()
on every GC'ed layer.
RemoteLayer::delete() returned Ok(()) unconditionally.
GC would then proceed by decrementing the resident size metric,
even though the layer is a RemoteLayer.
This patch makes the following changes:
- Rename PersistentLayer::delete() to delete_resident_layer_file().
That name is unambiguous.
- Make RemoteLayer::delete_resident_layer_file return an Err().
We would have uncovered this bug if we had done that from the start.
- Change GC / Timeline::delete_historic_layer check whether
the layer is remote or not, and only call delete_resident_layer_file()
if it's not remote. This brings us in line with how eviction does it.
- Add a regression test.
fixes https://github.com/neondatabase/neon/issues/3722
## Describe your changes
Rebase vendored PostgreSQL onto 14.7 and 15.2
## Issue ticket number and link
#3579
## Checklist before requesting a review
- [x] I have performed a self-review of my code.
- [x] 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?
- [x] If this PR requires public announcement, mark it with
/release-notes label and add several sentences in this section.
```
The version of PostgreSQL that we use is updated to 14.7 for PostgreSQL
14 and 15.2 for PostgreSQL 15.
```
these are happening in tests because of #3655 but they sure took some
time to appear.
makes the `Compaction failed, retrying in 2s: Cannot run compaction
iteration on inactive tenant` into a globally allowed error, because it
has been seen failing on different test cases.
## Describe your changes
test_on_demand_download is flaky because not waiting until created image
layer is transferred to S3.
test_tenants_with_remote_storage just leaves garbage at the end of
overwritten file.
Right solution for test_on_demand_download is to add some API call to
wait completion of synchronization with S3 (not just based on last
record LSN). But right now it is solved using sleep.
## Issue ticket number and link
#3209
## 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.
On the surface, this doesn't add much, but there are some benefits:
* We can do graceful shutdowns and thus record more code coverage data.
* We now have a foundation for the more interesting behaviors, e.g. "stop
accepting new connections after SIGTERM but keep serving the existing ones".
* We give the otel machinery a chance to flush trace events before
finally shutting down.
Repeatedly (twice) try to download the compaction targeted layers before actual
compaction. Adds tests for both L0 compaction downloading layers and image
creation downloading layers. Image creation support existed already.
Fixes#3591
Co-authored-by: Christian Schwarz <christian@neon.tech>
Refactor the tenant_size_model code. Segment now contains just the
minimum amount of information needed to calculate the size. Other
information that is useful for building up the segment tree, and for
display purposes, is now kept elsewhere. The code in 'main.rs' has a new
ScenarioBuilder struct for that.
Calculating which Segments are "needed" is now the responsibility of the
caller of tenant_size_mode, not part of the calculation itself. So it's
up to the caller to make all the decisions with retention periods for
each branch.
The output of the sizing calculation is now a Vec of SizeResults, rather
than a tree. It uses a tree representation internally, when doing the
calculation, but it's not exposed to the caller anymore.
Refactor the way the recursive calculation is performed.
Rewrite the code in size.rs that builds the Segment model. Get rid of
the intermediate representation with Update structs. Build the Segments
directly, with some local HashMaps and Vecs to track branch points to
help with that.
retention_period is now an input to gather_inputs(), rather than an
output.
Update pageserver http API: rename /size endpoint to /synthetic_size
with following parameters:
- /synthetic_size?inputs_only to get debug info;
- /synthetic_size?retention_period=0 to override cutoff that is used to
calculate the size;
pass header -H "Accept: text/html" to get HTML output, otherwise JSON is
returned
Update python tests and openapi spec.
---------
Co-authored-by: Anastasia Lubennikova <anastasia@neon.tech>
Co-authored-by: Joonas Koivunen <joonas@neon.tech>
