- Fix and improve comments
- Rename 'physical_size' local variable to 'resident_size' for clarity.
- Remove one 'unnecessary wait_for_upload' call. The
'wait_for_sk_commit_lsn_to_reach_remote_storage' call after shutting
down compute is sufficient.
Follow-up of https://github.com/neondatabase/neon/pull/3270 which made
an example from main README.md not working.
Fixes that, by adding a way to specify a default tenant now and modifies
the basic neon_local test to start postgres and check branching.
Not all neon_local commands are implemented, so not all README.md
contents is tested yet.
It's not OK to return early from within a PG_TRY-CATCH block. The
PG_TRY macro sets the global PG_exception_stack variable, and
PG_END_TRY restores it. If we jump out in between with "return NULL",
the PG_exception_stack is left to point to garbage. (I'm surprised the
comments in PG_TRY_CATCH don't warn about this.)
Add test that re-attaches tenant in pageserver while Postgres is
running. If the tenant is detached while compute is connected and
busy running queries, those queries will fail if they try to fetch any
pages. But when the tenant is re-attached, things should start working
again, without disconnecting the client <-> postgres connections.
Without this fix, this reproduced the segfault.
Fixes issue #3231
For every Python test, we start the storage first, and expect that
later, in the test, when we start a compute, it will work without
specific timeline and tenant creation or their IDs specified.
For that, we have a concept of "default" branch that was created on the
control plane level first, but that's not needed at all, given that it's
only Python tests that need it: let them create the initial timeline
during set-up.
Before, control plane started and stopped pageserver for timeline
creation, now Python harness runs an extra tenant creation request on
test env init.
I had to adjust the metrics test, turns out it registered the metrics
from the default tenant after an extra pageserver restart.
New model does not sent the metrics before the collection time happens,
and that was 30s before.
- Clean up redundant metric removal in TimelineMetrics::drop.
RemoteTimelineClientMetrics is responsible for cleaning up
REMOTE_OPERATION_TIME andREMOTE_UPLOAD_QUEUE_UNFINISHED_TASKS.
- Rename `pageserver_remote_upload_queue_unfinished_tasks` to
`pageserver_remote_timeline_client_calls_unfinished`. The new name
reflects that the metric is with respect to the entire call to remote
timeline client. This includes wait time in the upload queue and hence
it's a longer span than what `pageserver_remote_OPERATION_seconds`
measures.
- Add the `pageserver_remote_timeline_client_calls_started` histogram.
See the metric description for why we need it.
- Add helper functions `call_begin` etc to `RemoteTimelineClientMetrics`
to centralize the logic for updating the metrics above (they relate to
each other, see comments in code).
- Use these constructs to track ongoing downloads in
`pageserver_remote_timeline_client_calls_unfinished`
refs https://github.com/neondatabase/neon/issues/2029
fixes https://github.com/neondatabase/neon/issues/3249
closes https://github.com/neondatabase/neon/pull/3250
Closes https://github.com/neondatabase/neon/issues/3114
Adds more typization into errors that appear during protocol messages (`FeMessage`), postgres and walreceiver connections.
Socket IO errors are now better detected and logged with lesser (INFO, DEBUG) error level, without traces that they were logged before, when they were wrapped in anyhow context.
It was nice to have and useful at the time, but unfortunately the method
used to gather the profiling data doesn't play nicely with 'async'. PR
#3228 will turn 'get_page_at_lsn' function async, which will break the
profiling support. Let's remove it, and re-introduce some kind of
profiling later, using some different method, if we feel like we need it
again.
The synchronous 'tar' crate has required us to use block_in_place and
SyncIoBridge to work together with the async I/O in the client
connection. Switch to 'tokio-tar' crate that uses async I/O natively.
As part of this, move the CopyDataWriter implementation to
postgres_backend_async.rs. Even though it's only used in one place
currently, it's in principle generally applicable whenever you want to
use COPY out.
Unfortunately we cannot use the 'tokio-tar' as it is: the Builder
implementation requires the writer to have 'static lifetime. So we
have to use a modified version without that requirement. The 'static
lifetime was required just for the Drop implementation that writes
the end-of-archive sections if the Builder is dropped without calling
`finish`. But we don't actually want that behavior anyway; in fact
we had to jump through some hoops with the AbortableWrite hack to skip
those. With the modified version of 'tokio-tar' without that Drop
implementation, we don't need AbortableWrite either.
Co-authored-by: Kirill Bulatov <kirill@neon.tech>
Send this metric only when it is fully calculated.
Make consumption metrics more stable:
- Send per-timeline metrics only for active timelines.
- Adjust test assertions to make test_metric_collection test more stable.
The code in this change was extracted from #2595 (Heikki’s on-demand
download draft PR).
High-Level Changes
- New RemoteLayer Type
- On-Demand Download As An Effect Of Page Reconstruction
- Breaking Semantics For Physical Size Metrics
There are several follow-up work items planned.
Refer to the Epic issue on GitHub: https://github.com/neondatabase/neon/issues/2029
closes https://github.com/neondatabase/neon/pull/3013
Co-authored-by: Kirill Bulatov <kirill@neon.tech>
Co-authored-by: Christian Schwarz <christian@neon.tech>
New RemoteLayer Type
====================
Instead of downloading all layers during tenant attach, we create
RemoteLayer instances for each of them and add them to the layer map.
On-Demand Download As An Effect Of Page Reconstruction
======================================================
At the heart of pageserver is Timeline::get_reconstruct_data(). It
traverses the layer map until it has collected all the data it needs to
produce the page image. Most code in the code base uses it, though many
layers of indirection.
Before this patch, the function would use synchronous filesystem IO to
load data from disk-resident layer files if the data was not cached.
That is not possible with RemoteLayer, because the layer file has not
been downloaded yet. So, we do the download when get_reconstruct_data
gets there, i.e., “on demand”.
The mechanics of how the download is done are rather involved, because
of the infamous async-sync-async sandwich problem that plagues the async
Rust world. We use the new PageReconstructResult type to work around
this. Its introduction is the cause for a good amount of code churn in
this patch. Refer to the block comment on `with_ondemand_download()`
for details.
Breaking Semantics For Physical Size Metrics
============================================
We rename prometheus metric pageserver_{current,resident}_physical_size to
reflect what this metric actually represents with on-demand download.
This intentionally BREAKS existing grafana dashboard and the cost model data
pipeline. Breaking is desirable because the meaning of this metrics has changed
with on-demand download. See
https://docs.google.com/document/d/12AFpvKY-7FZdR5a4CaD6Ir_rI3QokdCLSPJ6upHxJBo/edit#
for how we will handle this breakage.
Likewise, we rename the new billing_metrics’s PhysicalSize => ResidentSize.
This is not yet used anywhere, so, this is not a breaking change.
There is still a field called TimelineInfo::current_physical_size. It
is now the sum of the layer sizes in layer map, regardless of whether
local or remote. To compute that sum, we added a new trait method
PersistentLayer::file_size().
When updating the Python tests, we got rid of
current_physical_size_non_incremental. An earlier commit removed it from
the OpenAPI spec already, so this is not a breaking change.
test_timeline_size.py has grown additional assertions on the
resident_physical_size metric.
Add new background job to collect billing metrics for each tenant and
send them to the HTTP endpoint.
Metrics are cached, so we don't send non-changed metrics.
Add metric collection config parameters:
metric_collection_endpoint (default None, i.e. disabled)
metric_collection_interval (default 60s)
Add test_metric_collection.py to test metric collection
and sending to the mocked HTTP endpoint.
Use port distributor in metric_collection test
review fixes: only update cache after metrics were send successfully, simplify code
disable metric collection if metric_collection_endpoint is not provided in config
Remote operations fail sometimes due to network failures or other
external reasons. Add retry logic to all the remote downloads, so that
a transient failure at pageserver startup or tenant attach doesn't
cause the whole tenant to be marked as Broken.
Like in the uploads retry logic, we print the failure to the log as a
WARNing after three retries, but keep retrying. We will retry up to 10
times now, before returning the error to the caller.
To test the retries, I created a new RemoteStorage wrapper that simulates
failures, by returning an error for the first N times that a remote
operation is performed. It can be enabled by setting a new
"test_remote_failures" option in the pageserver config file.
Fixes#3112
This splits the storage_sync2::schedule_index_file into two (public)
functions:
1. `schedule_index_upload_for_metadata_update`, for when the metadata
(e.g. disk_consistent_lsn or last_gc_cutoff) has changed, and
2. `schedule_index_upload_for_file_changes`, for when layer file uploads
or deletions have been scheduled.
We now keep track of whether there have been any uploads or deletions
since the last index-file upload, and skip the upload in
`schedule_index_upload_for_file_changes` if there haven't been any
changes. That allows us to call the function liberally in timeline.rs,
whenever layer file uploads or deletions might've been scheduled,
without starting a lot of unnecessary index file uploads.
GC was covered earlier by commit c262390214, but that missed that we
have the same problem with compaction.
- Refactor logical_size_calculation_task, moving the pieces that are
specific to try_spawn_size_init_task into that function.
This allows us to spawn additional size calculation tasks that are not
init size calculation tasks.
- As part of this refactoring, stop logging cancellations as errors.
They are part of regular operations.
Logging them as errors was inadvertently introduced in earlier commit
427c1b2e9661161439e65aabc173d695cfc03ab4
initial logical size calculation: if it fails, retry on next call
- Change tenant size model request code to spawn task_mgr tasks using
the refactored logical_size_calculation_task function.
Using a task_mgr task ensures that the calculation cannot outlive
the timeline.
- There are presumably still some subtle race conditions if a size
requests comes in at exactly the same time as a detach / delete
request.
- But that's the concern of diferent area of the code (e.g., tenant_mgr)
and requires holistic solutions, such as the proposed TenantGuard.
- Make size calculation cancellable using CancellationToken.
This is more of a cherry on top.
NB: the test code doesn't use this because we _must_ return from
the failpoint, because the failpoint lib doesn't allow to just
continue execution in combination with executing the closure.
This commit fixes the tests introduced earlier in this patch series.
This exacerbates the problem pointed out in the previous commit.
Why? Because with this patch, deleting a timeline also exposes the issue.
Extend the test to expose the problem.
This fixes all kinds of problems related to missing params,
like broken timestamps (due to `integer_datetimes`).
This solution is not ideal, but it will help. Meanwhile,
I'm going to dedicate some time to improving connection machinery.
Note that this **does not** fix problems with passing certain parameters
in a reverse direction, i.e. **from client to compute**. This is a
separate matter and will be dealt with in an upcoming PR.
I saw an excessive number of index file upload operations in
production, even when nothing on the timeline changes. It was because
our GC schedules index file upload if the GC cutoff LSN is advanced,
even if the GC had nothing else to do. The GC cutoff LSN marches
steadily forwards, even when there is no user activity on the
timeline, when the cutoff is determined by the time-based PITR
interval setting. To dial that down, only schedule index file upload
when GC is about to actually remove something.
Previously, the /v1/tenant/:tenant_id/timeline/:timeline_id/do_gc API
call performed a flush and compaction on the timeline before
GC. Change it not to do that, and change all the tests that used that
API to perform compaction explicitly.
The compaction happens at a slightly different point now. Previously,
the code performed the `refresh_gc_info_internal` step first, and only
then did compaction on all the timelines. I don't think that was what
was originally intended here. Presumably the idea with compaction was
to make some old layer files available for GC. But if we're going to
flush the current in-memory layer to disk, surely you would want to
include the newly-written layer in the compaction too. I guess this
didn't make any difference to the tests in practice, but in any case,
the tests now perform the flush and compaction before any of the GC
steps.
Some of the tests might not need the compaction at all, but I didn't
try hard to determine which ones might need it. I left it out from a
few tests that intentionally tested calling do_gc with an invalid
tenant or timeline ID, though.
We do the accounting exclusively after updating remote IndexPart successfully.
This is cleaner & more robust than doing it upon completion of
individual layer file uploads / deletions since we can uset .set()
insteaf of add()/sub().
NB: Originally, this work was intended to be part of #3013 but it
turns out that it's completely orthogonal.
So, spin it out into this PR for easier review.
Since this change is additive, it won't break anything.
Temporarily disable `test_seqscans` for remote projects; they acquire
too much space and time. We can try to reenable it back after switching
to per-test projects.
Closes https://github.com/neondatabase/neon/issues/1984
Closes https://github.com/neondatabase/neon/pull/2830
A follow-up of https://github.com/neondatabase/neon/pull/2830, I've
noticed that benchmarks failed again due to out of space issues.
Removes most of the pageserver and safekeeper files from disk after
every pytest suite run.
```
$ poetry run pytest -vvsk "test_tenant_redownloads_truncated_file_on_startup[local_fs]"
# ...
$ du -h test_output/test_tenant_redownloads_truncated_file_on_startup\[local_fs\]
# ...
104K test_output/test_tenant_redownloads_truncated_file_on_startup[local_fs]
$ poetry run pytest -vvsk "test_tenant_redownloads_truncated_file_on_startup[local_fs]" --preserve-database-files
# ...
$ du -h test_output/test_tenant_redownloads_truncated_file_on_startup\[local_fs\]
# ...
123M test_output/test_tenant_redownloads_truncated_file_on_startup[local_fs]
```
Co-authored-by: Bojan Serafimov <bojan.serafimov7@gmail.com>
This patch aims to fix some of the inconsistencies in error reporting,
for example "Internal error" or "Console request failed" instead of
"password authentication failed for user '<NAME>'".
refactor: use new type LayerFileName when referring to layer file names in PathBuf/RemotePath
Before this patch, we would sometimes carry around plain file names in
`Path` types and/or awkwardly "rebase" paths to have a unified
representation of the layer file name between local and remote.
This patch introduces a new type `LayerFileName` which replaces the use
of `Path` / `PathBuf` / `RemotePath` in the `storage_sync2` APIs.
Instead of holding a string, it contains the parsed representation of
the image and delta file name.
When we need the file name, e.g., to construct a local path or
remote object key, we construct the name ad-hoc.
`LayerFileName` is also serde {Dese,Se}rializable, and in an initial
version of this patch, it was supposed to be used directly inside
`IndexPart`, replacing `RemotePath`.
However,
commit 3122f3282f
Ignore backup files (ones with .n.old suffix) in download_missing
fixed handling of `*.old` backup file names in IndexPart, and we need
to carry that behavior forward.
The solution is to remove `*.old` backup files names during
deserialization. When we re-serialize the IndexPart, the `*.old` file
will be gone.
This leaks the `.old` file in the remote storage, but makes it safe
to clean it up later.
There is additional churn by a preliminary refactoring that got squashed
into this change:
split off LayerMap's needs from trait Layer into super trait
That refactoring renames `Layer` to `PersistentLayer` and splits off a subset
of the functions into a super-trait called `Layer`.
The upser trait implements just the functions needed by `LayerMap`, whereas
`PersisentLayer` adds the context of the pageserver.
The naming is imperfect as some functions that reside in `PersistentLayer`
have nothing persistence-specific to it. But it's a step in the right direction.
Increase table size four times to fix the following error:
```
______________________ test_seqscans[remote-100000-100-0] ______________________
test_runner/performance/test_seqscans.py:57: in test_seqscans
assert int(shared_buffers) < int(table_size)
E assert 536870912 < 181239808
E + where 536870912 = int(536870912)
E + and 181239808 = int(181239808)
```
536870912 / 181239808 ≈ 2.96
Closes https://github.com/neondatabase/neon/issues/3052
From what I could understand from the PR, we did not wait enough before
the attach failed.
Extended the wait period a bit and put a check for a status instead of
plain `sleep` to fail if we don't get the expected status.
This is rather a hack to resolve immediate issue:
https://github.com/neondatabase/neon/issues/3024
Properly cleaning this file from index part requires changes to
initialization of remote queue. Because we need to clean it up earlier
than we start warking around files.
With on-demand there will be no walk around layer files becase
download_missing is no longer needed, so I believe it will be
natural to unify this with load_layer_map
