We had a problem where almost all of the threads were waiting on a futex syscall. More specifically:
- `/metrics` handler was inside `TimelineCollector::collect()`, waiting on a mutex for a single Timeline
- This exact timeline was inside `control_file::FileStorage::persist()`, waiting on a mutex for Lazy initialization of `PERSIST_CONTROL_FILE_SECONDS`
- `PERSIST_CONTROL_FILE_SECONDS: Lazy<Histogram>` was blocked on `prometheus::register`
- `prometheus::register` calls `DEFAULT_REGISTRY.write().register()` to take a write lock on Registry and add a new metric
- `DEFAULT_REGISTRY` lock was already taken inside `DEFAULT_REGISTRY.gather()`, which was called by `/metrics` handler to collect all metrics
This commit creates another Registry with a separate lock, to avoid deadlock in a case where `TimelineCollector` triggers registration of new metrics inside default registry.
Creates new `pageserver_api` and `safekeeper_api` crates to serve as the
shared dependencies. Should reduce both recompile times and cold compile
times.
Decreases the size of the optimized `neon_local` binary: 380M -> 179M.
No significant changes for anything else (mostly as expected).
- Split postgres_ffi into two version specific files.
- Preserve pg_version in timeline metadata.
- Use pg_version in safekeeper code. Check for postgres major version mismatch.
- Clean up the code to use DEFAULT_PG_VERSION constant everywhere, instead of hardcoding.
- Parameterize python tests: use DEFAULT_PG_VERSION env and pg_version fixture.
To run tests using a specific PostgreSQL version, pass the DEFAULT_PG_VERSION environment variable:
'DEFAULT_PG_VERSION='15' ./scripts/pytest test_runner/regress'
Currently don't all tests pass, because rust code relies on the default version of PostgreSQL in a few places.
Part of the general work on improving pageserver logs.
Brief summary of changes:
* Remove `ApiError::from_err`
* Remove `impl From<anyhow::Error> for ApiError`
* Convert `ApiError::{BadRequest, NotFound}` to use `anyhow::Error`
* Note: `NotFound` has more verbose formatting because it's more
likely to have useful information for the receiving "user"
* Explicitly convert from `tokio::task::JoinError`s into
`InternalServerError`s where appropriate
Also note: many of the places where errors were implicitly converted to
500s have now been updated to return a more appropriate error. Some
places where it's not yet possible to distinguish the error types have
been left as 500s.
Follow-up to PR #2433 (b8eb908a). There's still a few more unresolved
locations that have been left as-is for the same compatibility reasons
in the original PR.
This commit does two things of note:
1. Bumps the bindgen dependency from `0.59.1` to `0.60.1`. This gets us
an actual error type from bindgen, so we can display what's wrong.
2. Adds `anyhow` as a build dependency, so our error message can be
prettier. It's already used heavily elsewhere in the crates in this
repo, so I figured the fact it's a build dependency doesn't matter
much.
I ran into this from running `cargo <cmd>` without running `make` first.
Here's a comparison of the compiler output in those two cases.
Before this commit:
```
error: failed to run custom build command for `postgres_ffi v0.1.0 ($repo_path/libs/postgres_ffi)`
Caused by:
process didn't exit successfully: `$repo_path/target/debug/build/postgres_ffi-2f7253b3ad3ca840/build-script-build` (exit status: 101)
--- stdout
cargo:rerun-if-changed=bindgen_deps.h
--- stderr
bindgen_deps.h:7:10: fatal error: 'c.h' file not found
bindgen_deps.h:7:10: fatal error: 'c.h' file not found, err: true
thread 'main' panicked at 'Unable to generate bindings: ()', libs/postgres_ffi/build.rs:135:14
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
```
After this commit:
```
error: failed to run custom build command for `postgres_ffi v0.1.0 ($repo_path/libs/postgres_ffi)`
Caused by:
process didn't exit successfully: `$repo_path/target/debug/build/postgres_ffi-e01fb59602596748/build-script-build` (exit status: 1)
--- stdout
cargo:rerun-if-changed=bindgen_deps.h
--- stderr
bindgen_deps.h:7:10: fatal error: 'c.h' file not found
Error: Unable to generate bindings
Caused by:
clang diagnosed error: bindgen_deps.h:7:10: fatal error: 'c.h' file not found
```
Instead of spawning helper threads, we now use Tokio tasks. There
are multiple Tokio runtimes, for different kinds of tasks. One for
serving libpq client connections, another for background operations
like GC and compaction, and so on. That's not strictly required, we
could use just one runtime, but with this you can still get an
overview of what's happening with "top -H".
There's one subtle behavior in how TenantState is updated. Before this
patch, if you deleted all timelines from a tenant, its GC and
compaction loops were stopped, and the tenant went back to Idle
state. We no longer do that. The empty tenant stays Active. The
changes to test_tenant_tasks.py are related to that.
There's still plenty of synchronous code and blocking. For example, we
still use blocking std::io functions for all file I/O, and the
communication with WAL redo processes is still uses low-level unix
poll(). We might want to rewrite those later, but this will do for
now. The model is that local file I/O is considered to be fast enough
that blocking - and preventing other tasks running in the same thread -
is acceptable.
We had a pattern like this:
match remote_storage {
GenericRemoteStorage::Local(storage) => {
let source = storage.remote_object_id(&file_path)?;
...
storage
.function(&source, ...)
.await
},
GenericRemoteStorage::S3(storage) => {
... exact same code as for the Local case ...
},
This removes the code duplication, by allowing you to call the functions
directly on GenericRemoteStorage.
Also change RemoveObjectId to be just a type alias for String. Now that
the callers of GenericRemoteStorage functions don't know whether they're
dealing with the LocalFs or S3 implementation, RemoveObjectId must be the
same type for both.
Another preparatory commit for pg15 support:
* generate bindings for both pg14 and pg15;
* update Makefile and CI scripts: now neon build depends on both PostgreSQL versions;
* some code refactoring to decrease version-specific dependencies.
* Add submodule postgres-15
* Support pg_15 in pgxn/neon
* Renamed zenith -> neon in Makefile
* fix name of codestyle check
* Refactor build system to prepare for building multiple Postgres versions.
Rename "vendor/postgres" to "vendor/postgres-v14"
Change Postgres build and install directory paths to be version-specific:
- tmp_install/build -> pg_install/build/14
- tmp_install/* -> pg_install/14/*
And Makefile targets:
- "make postgres" -> "make postgres-v14"
- "make postgres-headers" -> "make postgres-v14-headers"
- etc.
Add Makefile aliases:
- "make postgres" to build "postgres-v14" and in future, "postgres-v15"
- similarly for "make postgres-headers"
Fix POSTGRES_DISTRIB_DIR path in pytest scripts
* Make postgres version a variable in codestyle workflow
* Support vendor/postgres-v15 in codestyle check workflow
* Support postgres-v15 building in Makefile
* fix pg version in Dockerfile.compute-node
* fix kaniko path
* Build neon extensions in version-specific directories
* fix obsolete mentions of vendor/postgres
* use vendor/postgres-v14 in Dockerfile.compute-node.legacy
* Use PG_VERSION_NUM to gate dependencies in inmem_smgr.c
* Use versioned ECR repositories and image names for compute-node.
The image name format is compute-node-vXX, where XX is postgres major version number.
For now only v14 is supported.
Old format unversioned name (compute-node) is left, because cloud repo depends on it.
* update vendor/postgres submodule url (zenith->neondatabase rename)
* Fix postgres path in python tests after rebase
* fix path in regress test
* Use separate dockerfiles to build compute-node:
Dockerfile.compute-node-v15 should be identical to Dockerfile.compute-node-v14 except for the version number.
This is a hack, because Kaniko doesn't support build ARGs properly
* bump vendor/postgres-v14 and vendor/postgres-v15
* Don't use Kaniko cache for v14 and v15 compute-node images
* Build compute-node images for different versions in different jobs
Co-authored-by: Heikki Linnakangas <heikki@neon.tech>
The code correctly detected too short and too long inputs, but the error
message was bogus for the case the input stream was too long:
Error: Provided stream has actual size 5 fthat is smaller than the given stream size 4
That check was only supposed to check for too small inputs, but it in
fact caught too long inputs too. That was good, because the check
below that that was supposed to check for too long inputs was in fact
broken, and never did anything. It tried to read input a buffer of
size 0, to check if there is any extra data, but reading to a
zero-sized buffer always returns 0.
Previously, proxy didn't forward auxiliary `options` parameter
and other ones to the client's compute node, e.g.
```
$ psql "user=john host=localhost dbname=postgres options='-cgeqo=off'"
postgres=# show geqo;
┌──────┐
│ geqo │
├──────┤
│ on │
└──────┘
(1 row)
```
With this patch we now forward `options`, `application_name` and `replication`.
Further reading: https://www.postgresql.org/docs/current/libpq-connect.htmlFixes#1287.
`latest_gc_cutoff_lsn` tracks the cutoff point where GC has been
performed. Anything older than the cutoff might already have been GC'd
away, and cannot be queried by get_page_at_lsn requests. It's
protected by an RWLock. Whenever a get_page_at_lsn requests comes in,
it first grabs the lock and reads the current `latest_gc_cutoff`, and
holds the lock it until the request has been served. The lock ensures
that GC doesn't start concurrently and remove page versions that we
still need to satisfy the request.
With the lock, get_page_at_lsn request could potentially be blocked
for a long time. GC only holds the lock in exclusive mode for a short
duration, but depending on how whether the RWLock is "fair", a read
request might be queued behind the GC's exclusive request, which in
turn might be queued behind a long-running read operation, like a
basebackup. If the lock implementation is not fair, i.e. if a reader
can always jump the queue if the lock is already held in read mode,
then another problem arises: GC might be starved if a constant stream
of GetPage requests comes in.
To avoid the long wait or starvation, introduce a Read-Copy-Update
mechanism to replace the lock on `latest_gc_cutoff_lsn`. With the RCU,
reader can always read the latest value without blocking (except for a
very short duration if the lock protecting the RCU is contended;
that's comparable to a spinlock). And a writer can always write a new
value without waiting for readers to finish using the old value. The
old readers will continue to see the old value through their guard
object, while new readers will see the new value.
This is purely theoretical ATM, we don't have any reports of either
starvation or blocking behind GC happening in practice. But it's
simple to fix, so let's nip that problem in the bud.
`///` is used for comments on the *next* code that follows, so the comment
actually applied to the `use std::collections::BTreeMap;` line that follows.
rustfmt complained about that:
error: an inner attribute is not permitted following an outer doc comment
--> /home/heikki/git-sandbox/neon/libs/utils/src/seqwait_async.rs:7:1
|
5 | ///
| --- previous doc comment
6 |
7 | #![warn(missing_docs)]
| ^^^^^^^^^^^^^^^^^^^^^^ not permitted following an outer attribute
8 |
9 | use std::collections::BTreeMap;
| ------------------------------- the inner attribute doesn't annotate this `use` import
|
= note: inner attributes, like `#![no_std]`, annotate the item enclosing them, and are usually found at the beginning of source files
help: to annotate the `use` import, change the attribute from inner to outer style
|
7 - #![warn(missing_docs)]
7 + #[warn(missing_docs)]
|
`//!` is the correct syntax for comments that apply to the whole file.
Re-export only things that are used by other modules.
In the future, I'm imagining that we run bindgen twice, for Postgres
v14 and v15. The two sets of bindings would go into separate
'bindings_v14' and 'bindings_v15' modules.
Rearrange postgres_ffi modules.
Move function, to avoid Postgres version dependency in timelines.rs
Move function to generate a logical-message WAL record to postgres_ffi.
The pg_control_ffi.h name implies that it only includes stuff related to
pg_control.h. That's mostly true currently, but really the point of the
file is to include everything that we need to generate Rust definitions
from.
Ref #1902.
- Track the layered timeline's `physical_size` using `pageserver_current_physical_size` metric when updating the layer map.
- Report the local timeline's `physical_size` in timeline GET APIs.
- Add `include-non-incremental-physical-size` URL flag to also report the local timeline's `physical_size_non_incremental` (similar to `logical_size_non_incremental`)
- Add a `UIntGaugeVec` and `UIntGauge` to represent `u64` prometheus metrics
Co-authored-by: Dmitry Rodionov <dmitry@neon.tech>
[proxy] Add the `password hack` authentication flow
This lets us authenticate users which can use neither
SNI (due to old libpq) nor connection string `options`
(due to restrictions in other client libraries).
Note: `PasswordHack` will accept passwords which are not
encoded in base64 via the "password" field. The assumption
is that most user passwords will be valid utf-8 strings,
and the rest may still be passed via "password_".
