# Which Problems Are Solved
To integrate river as a task queue we need to ensure the migrations of
river are executed.
# How the Problems Are Solved
- A new schema was added to the Zitadel database called "queue"
- Added a repeatable setup step to Zitadel which executes the
[migrations of
river](https://riverqueue.com/docs/migrations#go-migration-api).
# Additional Changes
- Added more hooks to the databases to properly set the schema for the
task queue
# Additional Context
- Closes https://github.com/zitadel/zitadel/issues/9280
# Which Problems Are Solved
Zitadel currently uses 3 database pool, 1 for queries, 1 for pushing
events and 1 for scheduled projection updates. This defeats the purpose
of a connection pool which already handles multiple connections.
During load tests we found that the current structure of connection
pools consumes a lot of database resources. The resource usage dropped
after we reduced the amount of database pools to 1 because existing
connections can be used more efficiently.
# How the Problems Are Solved
Removed logic to handle multiple connection pools and use a single one.
# Additional Changes
none
# Additional Context
part of https://github.com/zitadel/zitadel/issues/8352
# Which Problems Are Solved
If many events are written to the same aggregate id it can happen that
zitadel [starts to retry the push
transaction](48ffc902cc/internal/eventstore/eventstore.go (L101))
because [the locking
behaviour](48ffc902cc/internal/eventstore/v3/sequence.go (L25))
during push does compute the wrong sequence because newly committed
events are not visible to the transaction. These events impact the
current sequence.
In cases with high command traffic on a single aggregate id this can
have severe impact on general performance of zitadel. Because many
connections of the `eventstore pusher` database pool are blocked by each
other.
# How the Problems Are Solved
To improve the performance this locking mechanism was removed and the
business logic of push is moved to sql functions which reduce network
traffic and can be analyzed by the database before the actual push. For
clients of the eventstore framework nothing changed.
# Additional Changes
- after a connection is established prefetches the newly added database
types
- `eventstore.BaseEvent` now returns the correct revision of the event
# Additional Context
- part of https://github.com/zitadel/zitadel/issues/8931
---------
Co-authored-by: Tim Möhlmann <tim+github@zitadel.com>
Co-authored-by: Livio Spring <livio.a@gmail.com>
Co-authored-by: Max Peintner <max@caos.ch>
Co-authored-by: Elio Bischof <elio@zitadel.com>
Co-authored-by: Stefan Benz <46600784+stebenz@users.noreply.github.com>
Co-authored-by: Miguel Cabrerizo <30386061+doncicuto@users.noreply.github.com>
Co-authored-by: Joakim Lodén <Loddan@users.noreply.github.com>
Co-authored-by: Yxnt <Yxnt@users.noreply.github.com>
Co-authored-by: Stefan Benz <stefan@caos.ch>
Co-authored-by: Harsha Reddy <harsha.reddy@klaviyo.com>
Co-authored-by: Zach H <zhirschtritt@gmail.com>
* fix(db): add additional connection pool for projection spooling
* use correct connection pool for projections
---------
Co-authored-by: Livio Spring <livio.a@gmail.com>
This implementation increases parallel write capabilities of the eventstore.
Please have a look at the technical advisories: [05](https://zitadel.com/docs/support/advisory/a10005) and [06](https://zitadel.com/docs/support/advisory/a10006).
The implementation of eventstore.push is rewritten and stored events are migrated to a new table `eventstore.events2`.
If you are using cockroach: make sure that the database user of ZITADEL has `VIEWACTIVITY` grant. This is used to query events.
