One of our most flaky and most anoying tests is
multi_cluster_management. It usually fails like this:
```diff
SELECT citus_disable_node('localhost', :worker_2_port);
citus_disable_node
--------------------
(1 row)
SELECT public.wait_until_metadata_sync(60000);
+WARNING: waiting for metadata sync timed out
wait_until_metadata_sync
--------------------------
(1 row)
```
This tries to address that by hardening wait_until_metadata_sync. I
believe the reason for this warning is that there is a race condition in
wait_until_metadata_sync. It's possible for the pre-check to fail, then
have the maintenance daemon send a notification. And only then have the
backend start to listen. I tried to fix it in two ways:
1. First run LISTEN, and only then read do the pre-check.
2. If we time out, check again just to make sure that we did not miss
the notification somehow. And don't show a warning if all metadata is
synced after the timeout.
It's hard to know for sure that this fixes it because the test is not
repeatable and I could not reproduce it locally. Let's just hope for the
best.
---------
Co-authored-by: Onur Tirtir <onurcantirtir@gmail.com>
Sometimes multi_reference_table failed in CI like this:
```diff
\c - - - :master_port
DROP INDEX reference_schema.reference_index_2;
\c - - - :worker_1_port
SELECT "Column", "Type", "Modifiers" FROM table_desc WHERE relid='reference_schema.reference_table_ddl_1250019'::regclass;
- Column | Type | Modifiers
----------------------------------------------------------------------
- value_2 | double precision | default 25.0
- value_3 | text | not null
- value_4 | timestamp without time zone |
- value_5 | double precision |
-(4 rows)
-
+ERROR: schema "citus_local_table_queries" does not exist
\di reference_schema.reference_index_2*
List of relations
Schema | Name | Type | Owner | Table
```
Source:
https://github.com/citusdata/citus/actions/runs/6707535961/attempts/2#summary-18226879513
Reading from table_desc apparantly has an issue that if the schema gets
deleted from one of the items, while it is being read that we get such
an error.
This change fixes that by not running multi_reference_table in parallel
with citus_local_tables_queries anymore.
I just enhanced the existing code to check if the relation is an index
belonging to a distributed table.
If so the shardId is appended to relation (index) name and the *_size
function are executed as before.
There is a change in an extern function:
`extern StringInfo GenerateSizeQueryOnMultiplePlacements(...)`
It's possible to create a new function and deprecate this one later if
compatibility is an issue.
Fixes https://github.com/citusdata/citus/issues/6496.
DESCRIPTION: Allows using Citus size functions on distributed tables
indexes.
---------
Co-authored-by: Onur Tirtir <onurcantirtir@gmail.com>
Sometimes validate constraint would fail like this:
```diff
validatable_constraint_8000016 | t
(10 rows)
DROP TABLE constrained_table;
+ERROR: deadlock detected
+DETAIL: Process 16602 waits for ShareRowExclusiveLock on relation 56258 of database 16384; blocked by process 16601.
+Process 16601 waits for AccessShareLock on relation 56120 of database 16384; blocked by process 16602.
+HINT: See server log for query details.
DROP TABLE referenced_table CASCADE;
DROP TABLE referencing_table;
DROP SCHEMA validate_constraint CASCADE;
-NOTICE: drop cascades to 3 other objects
+NOTICE: drop cascades to 4 other objects
DETAIL: drop cascades to type constraint_validity
drop cascades to view constraint_validations_in_workers
drop cascades to view constraint_validations
+drop cascades to table constrained_table
SET search_path TO DEFAULT;
```
Source:
https://github.com/citusdata/citus/actions/runs/6708383699?pr=7291
This change fixes that by not running together with the
foreign_key_to_reference_table test anymore. In passing it also
simplifies dropping of the test its resources.
Making tasks in CI required before merging to master is important and
useful. The way this works is by saving the exact names of the required
tasks in the admin interface of the repo. It has a search box to add
them so it's not completely horrible, but doing so is quite a hassle
since we have so many jobs. So limiting the amount of churn in this list
of required jobs is quite useful.
This changes the names of tasks to only include the major versions of
Postgres, not the minor ones. Otherwise the next time we bump the minor
versions we would have to remove and re-add each of the jobs.
DESCRIPTION: This change starts a maintenance deamon at the time of
server start if there is a designated main database.
This is the code flow:
1. User designates a main database:
`ALTER SYSTEM SET citus.main_db = "myadmindb";`
2. When postmaster starts, in _PG_Init, citus calls
`InitializeMaintenanceDaemonForMainDb`
This function registers a background worker to run
`CitusMaintenanceDaemonMain `with `databaseOid = 0 `
3. `CitusMaintenanceDaemonMain ` takes some special actions when
databaseOid is 0:
- Gets the citus.main_db value.
- Connects to the citus.main_db
- Now the `MyDatabaseId `is available, creates a hash entry for it.
- Then follows the same control flow as for a regular db,
When debugging postgres it is quite hard to get to the source for
`errfinish` in `elog.c`. Instead of relying on the developer to set a
breakpoint in the `elog.c` file for `errfinish` for `elevel == ERROR`,
this change adds the breakpoint to `.gdbinit`. This makes sure that
whenever a debugger is attached to a postgres backend it will break on
postgres errors.
When attaching the debugger a small banner is printed that explains how
to disable the breakpoint.
HasDistributionKey & HasDistributionKeyCacheEntry returns true when the
corresponding table has a distribution key, the comments state the
opposite,
which should be fixed.
Signed-off-by: Zhao Junwang <zhjwpku@gmail.com>
Co-authored-by: Onur Tirtir <onurcantirtir@gmail.com>
There was a bug reported for previous versions of Citus where
shard\_size was returning NULL for tables with spaces in them. It works
fine on the main branch though, but I'm still adding a test for this to
the main branch because it seems a good test to have.
During the creation of the devcontainer we need to add a ppa repository,
which is easiest done via software-properies-common. As turns out this
installes pkexec into the container as a side effect.
When vscode tries to attach a debugger it first checks if pkexec is
installed as this gives a nicer popup asking for elevation of rights to
attach to the process. However, since dev containers don't have a
windowing system running pkexec isn't working as expected and thus
prevents the debugger from attaching.
Without pkexec in the container vscode 'falls back' to plain old sudo
which we can run passwordless in the container.
For pkexec to be removed we need to first purge
software-propertied-common as well as autoremove all packages that were
installed due to the installation of said package. By performing this
all in one step we minimize the size of the layer we are creating.
DESCRIPTION: Send keepalive messages during the logical replication
phase of large shard splits to avoid timeouts.
During the logical replication part of the shard split process, split
decoder filters out the wal records produced by the initial copy. If the
number of wal records is big, then split decoder ends up processing for
a long time before sending out any wal records through pgoutput. Hence
the wal receiver may time out and restarts repeatedly causing our split
driver code catch up logic to fail.
Notes:
1. If the wal_receiver_timeout is set to a very small number e.g. 600ms,
it may time out before receiving the keepalives. My tests show that this
code works best when the` wal_receiver_timeout `is set to 1minute, which
is the default value.
2. Once a logical replication worker time outs, a new one gets launched.
The new logical replication worker sets the pg_stat_subscription columns
to initial values. E.g. the latest_end_lsn is set to 0. Our driver logic
in `WaitForGroupedLogicalRepTargetsToCatchUp` can not handle LSN value
to go back. This is the main reason for it to get stuck in the infinite
loop.
This change adds a devcontainer configuration to the Citus project. This
devcontainer allows for quick generation of isolated development
environments, either local on the machine of a developer or in a cloud,
like github codepaces.
The devcontainer is updated automatically by github actions when its
configuration changes.
For more detailed instructions on how to quickstart the development in a
container see CONTRIBUTING.md
DESCRIPTION: Fix leaking of memory and memory contexts in Foreign
Constraint Graphs
Previously, every time we (re)created the Foreign Constraint
Relationship Graph, we created a new Memory Context while loosing a
reference to the previous context. This old context could still have
left over memory in there causing a memory leak.
With this patch we statically have one memory context that we lazily
initialize the first time we create our foreign constraint relationship
graph. On every subsequent creation, beside destroying our previous
hashmap we also reset our memory context to remove any left over
references.
This commit aims to add a comprehensive guide that covers all essential
aspects of Citus, including planning, execution, locking mechanisms,
shard moves, 2PC, and many other major components of Citus.
Co-authored-by: Marco Slot <marco.slot@gmail.com>
When testing rolling Citus upgrades, coordinator should not be upgraded
until we upgrade all the workers.
---------
Co-authored-by: Jelte Fennema-Nio <github-tech@jeltef.nl>
DESCRIPTION: Shard moves/isolate report LSN's in lsn format
While investigating an issue with our catchup mechanism on certain
postgres versions we noticed we print LSN's in the format of the native
long type. This is an uncommon representation for LSN's in postgres
logs.
This patch changes the output of our log message to go from the long
type representation to the native LSN type representation. Making it
easier for postgres users to recognize and compare LSN's with other
related reports.
example of new output:
```
2023-09-25 17:28:47.544 CEST [11345] LOG: The LSN of the target subscriptions on node localhost:9701 have increased from 0/0 to 0/E1ED20F8 at 2023-09-25 17:28:47.544165+02 where the source LSN is 1/415DCAD0
```
If you make a fresh install make clean is not
required. However, if you install before, without
a make install, one can get errors
---------
Co-authored-by: aykut-bozkurt <51649454+aykut-bozkurt@users.noreply.github.com>
When cdc got added the makefiles hardcoded the `.so` extension instead
of using the platform specifc `$(DLSUFFIX)` variable used by `pgxs.mk`.
Also don't remove installed cdc artifacts on `make clean`.
This was sometimes failing when running locally due to some local shard
still existing due to. This fixes that. We normally silence all
`drop schema cascade` output like this anyway to avoid unnecessary
diffs when modifying a test later on.
centos 7 and oracle 7 is not being supported for newer releases by
Postgres. Therefore, getting package download errors in packaging
pipelines.
This PR removes el/7 and ol/7 Postgres 16 pipelines
DESCRIPTION: Adds support for ALTER DATABASE <db_name> SET .. statement
propagation
SET statements in Postgres has a common structure which is already being
used in Alter Function
statement.
In this PR, I added a util file; citus_setutils and made it usable for
both for
alter database<db_name>set .. and alter function ... set ... statements.
With this PR, below statements will be propagated
```sql
ALTER DATABASE name SET configuration_parameter { TO | = } { value | DEFAULT }
ALTER DATABASE name SET configuration_parameter FROM CURRENT
ALTER DATABASE name RESET configuration_parameter
ALTER DATABASE name RESET ALL
```
Additionally, there was a bug in processing float values in the common
code block.
I fixed this one as well
Previous
```C
case T_Float:
{
appendStringInfo(buf, " %s", strVal(value));
break;
}
```
Now
```C
case T_Float:
{
appendStringInfo(buf, " %s", nodeToString(value));
break;
}
```
DESCRIPTION: Adds ALTER DATABASE WITH ... and REFRESH COLLATION VERSION
support
This PR adds supports for basic ALTER DATABASE statements propagation
support. Below statements are supported:
ALTER DATABASE <database_name> with IS_TEMPLATE <true/false>;
ALTER DATABASE <database_name> with CONNECTION LIMIT <integer_value>;
ALTER DATABASE <database_name> REFRESH COLLATION VERSION;
---------
Co-authored-by: Jelte Fennema-Nio <jelte.fennema@microsoft.com>
We currently don't support propagating these options in Citus
Relevant PG commits:
https://github.com/postgres/postgres/commit/e3ce2dehttps://github.com/postgres/postgres/commit/3d14e17
Limitation:
We also need to take care of generated GRANT statements by dependencies
in attempt to distribute something else. Specifically, this part of the
code in `GenerateGrantRoleStmtsOfRole`:
```
grantRoleStmt->admin_opt = membership->admin_option;
```
In PG16, membership also has `inherit_option` and `set_option` which
need to properly be part of the `grantRoleStmt`. We can skip for now
since #7164 will take care of this soon, and also this is not an
expected use-case.
Jelte Fennema-Nio
Cédric Villemain
Gokhan Gulbiz
Emel Şimşek
Nils Dijk
Benjamin O
Naisila Puka
zhjwpku
Onur Tirtir
Gürkan İndibay
Önder Kalacı
dependabot[bot]
Hanefi Onaldi
Teresa Giacomini
aykut-bozkurt