# 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
* fix(db): add additional connection pool for projection spooling
* use correct connection pool for projections
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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.
feat(storage): read only transactions for queries (#6415)
* fix: tests
* bastle wie en grosse
* fix(database): scan as callback
* fix tests
* fix merge failures
* remove as of system time
* refactor: remove unused test
* refacotr: remove unused lines
