Based on Konstantin's original patch (PR #275), but I introduced helper
functions for serializing/deserializing the different kinds of
ObjectValues, which made it more pleasant to use, as the deserialization
checks are now performed in the helper functions.
Add back code to parse transaction commit and abort records, and in
particular the list of dropped relations in them. Add 'put_unlink'
function to the Timeline trait and implementation. We had the code to
handle dropped relations in the GC code and elsewhere in ObjectRepository
already, but there was nothing to create the RelationSizeEntry::Unlink
tombstone entries until now. Also add a test to check that GC correctly
removes all page versions of a dropped relation.
Implements https://github.com/zenithdb/zenith/issues/232, except for the
"orphaned" rels.
Reviewed-by: Konstantin Knizhnik
Some of these were related to handling various WAL records that are not
related to any relations, like pg_multixact updates. These should have
been removed in the revert commit 6a9c036ac1, but I missed them.
Also, we didn't anything with commit/abort records. We will start
parsing commit/abort records in the next commit, but seems better to
add that from clean slate.
Reviewed-by: Konstantin Knizhnik
Without this step, the page versions won't actually be removed, they're
just marked for deletion on the next RocksDB "merge" or "compact"
operation.
Author: Konstantin Knizhnik
- Print the number of dropped relations, and the number of relations
encountered overall.
- If a block has only one page version, the latest one, don't count it as
a "truncated" version history. Only count pages for which we actually
removed some old versions.
- Change "last" to "latest" in variable names and comments. "Last" could
be interpreted as "oldest", but here it means "newest".
- Add a comment noting that the GC code depends on get_page_at_lsn_nowait
to store the materialized page version in the repository.
- Change "last" to "latest" in variable names for clarity. "Last" could
be interpreted as the oldest, but here it means newest.
This patch aims to:
* Unify connection & querying logic of ZenithPagerserver and Postgres.
* Mitigate changes to transaction machinery introduced in `psycopg2 >= 2.9`.
Now it's possible to acquire db connection using the corresponding
method:
```python
pg = postgres.create_start('main')
conn = pg.connect()
...
conn.close()
```
This pattern can be further improved with the help of `closing`:
```python
from contextlib import closing
pg = postgres.create_start('main')
with closing(pg.connect()) as conn:
...
```
All connections produced by this method will have autocommit
enabled by default.
The clippy maintainers have not provided an easy way for projects to
configure the set of lints they would like enabled/disabled. It's
particularly bad for projects using workspaces, which can easily lead to
duplicated clippy annotations for every crate, library, binary, etc.
Add a shell script that runs clippy, with a few unhelpful lints
disabled:
new_without_default
manual_range_contains
comparison_chain
If you save this in your path under the name "cargo-zclippy" (or
whatever name you like), then you can run it as "cargo zclippy" from the
shell prompt. If your text editor has rust-analyzer integration, you can
also use this new command as a replacement for "cargo check" or "cargo
clippy" and see clippy warnings and errors right in the editor.
To simplify cloud ops, allow configuration via file.
toml is used as the config format, and the file is stored in the working
directory.
Arguments used at initialization are saved in the config file.
Config file params may be overridden by CLI arguments.
Use CLI args instead of environment variables to parameterize the
working directory and postgres distirbution.
Before this change, there was a mixture of environment variables and CLI
arguments that needed to be set. Moving to a single input simplifies
cloud configuration management.
The bool::then function was added in Rust 1.50. I'm still using 1.48 on
my laptop. We haven't decided what Rust version we will require
(https://github.com/zenithdb/zenith/issues/138), and I'll probably need
to upgrade sooner or later, but this will do for now.
It's not realistic to enable full-blown type checks
within test_runner's codebase, since the amount of
warnings revealed by mypy is overwhelming.
Tests are supposed to be easy to use, so we can't
cripple everybody's workflow for the sake of imaginary benefit.
Ultimately, the purpose of this attempt is three-fold:
* Facilitate code navigation when paired with python-language-server.
* Make method signatures apparent to a fellow programmer.
* Occasionally catch some obvious type errors.
Clear a clippy warning about manual flatten.
This isn't good error handling, but panicking is probably better than
spinning forever if stdin returns EOF.
Previously, transaction commit could happen regardless of whether
pageserver has caught up or not. This patch aims to fix that.
There are two notable changes:
1. ComputeControlPlane::new_node() now sets the
`synchronous_standby_names = 'pageserver'` parameter to delay
transaction commit until pageserver acting as a standby has
fetched and ack'd a relevant portion of WAL.
2. pageserver now has to:
- Specify the `application_name = pageserver` which matches the
one in `synchronous_standby_names`.
- Properly reply with the ack'd LSNs.
This means that some tests don't need sleeps anymore.
TODO: We should probably make this behavior configurable.
Fixes#187.
Now postgres_backend communicates with the client, passing queries to the
provided handler; we have two currently, for wal_acceptor and pageserver.
Now BytesMut is again used for writing data to avoid manual message length
calculation.
ref #118
