ObjectTypeManager introspection not cached #520

New Issue

MrUnknownDE · 2026-04-05T16:39:14+02:00

MrUnknownDE commented

2026-04-05 16:39:14 +02:00

Originally created by @jetseverschuren-novoserve on 1/20/2026

NetBox Edition

NetBox Community

NetBox Version

v4.5.0

Python Version

3.12

Steps to Reproduce

Enable DB logging:

ALTER SYSTEM SET log_min_duration_statement = 0;
SELECT pg_reload_conf();

Load basically any page with data, for example http://localhost:8080/dcim/racks/ or http://localhost:8080/api/dcim/racks/ (GraphQL not tested)
Check Postgres logs for queries on table pg_catalog.pg_class

Expected Behavior

I'd expect only one introspection query to happen per worker, and the results to be cached until a restart or a migration

Observed Behavior

Per HTTP request multiple introspection calls are made to the database. For REST calls this is usually two or three, for a frontend page load I've observed up to 11.

The issue seems to come from netbox/core/models/object_types.py. Patching out the below lines on our staging environment completely eliminated the introspection calls to our database.
3efa23cf8f/netbox/core/models/object_types.py (L72-L75)

After analysis with PgBadger these queries were both the most frequent query and also the heaviest query for our Postgres instance. Some quick and dirty benchmarks of get_for_model showed ~44ms with the introspection in place, and ~3ms with it patched out.

*Originally created by @jetseverschuren-novoserve on 1/20/2026* ### NetBox Edition NetBox Community ### NetBox Version v4.5.0 ### Python Version 3.12 ### Steps to Reproduce 1. Enable DB logging: ```sql ALTER SYSTEM SET log_min_duration_statement = 0; SELECT pg_reload_conf(); ``` 2. Load basically any page with data, for example http://localhost:8080/dcim/racks/ or http://localhost:8080/api/dcim/racks/ (GraphQL not tested) 3. Check Postgres logs for queries on table `pg_catalog.pg_class` ### Expected Behavior I'd expect only one introspection query to happen per worker, and the results to be cached until a restart or a migration ### Observed Behavior Per HTTP request multiple introspection calls are made to the database. For REST calls this is usually two or three, for a frontend page load I've observed up to 11. The issue seems to come from `netbox/core/models/object_types.py`. Patching out the below lines on our staging environment completely eliminated the introspection calls to our database. https://github.com/netbox-community/netbox/blob/3efa23cf8f4c5de84617072a19833b46ad255b12/netbox/core/models/object_types.py#L72-L75 After analysis with PgBadger these queries were both the most frequent query and also the heaviest query for our Postgres instance. Some quick and dirty benchmarks of `get_for_model` showed ~44ms with the introspection in place, and ~3ms with it patched out.

MrUnknownDE closed this issue

2026-04-05 16:39:14 +02:00

Sign in to join this conversation.

Branches Tags

main

21455-sql-indexes-audit

21357-register-model-actions

feature

20924-plugin-ui-components

21766-improve-test-coverage-for-sortable-table-columns

21157-export-template-public-models

21025-pre-render-config-contexts

21364-swagger

feature-ip-prefix-link

20911-dropdown-3

fix_module_substitution

21160-filterset

20911-dropdown-2

20044-elevation-stuck-lightmode

7604-filter-modifiers-v3

20660-script-load

19724-graphql

14884-script

19720-macaddress-interface-generic-relation

fix-19669-api-image-download

7604-filter-modifiers

19275-fixes-interface-bulk-edit

fix-17794-get_field_value_return_list

11507-show-aggregate-and-rir-on-api

9583-add_column_specific_search_field_to_tables

No Label netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox netbox severity: medium severity: medium severity: medium severity: medium severity: medium severity: medium severity: medium severity: medium severity: medium severity: medium severity: medium severity: medium status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted status: accepted type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug type: bug

1 Participants

Notifications

Due Date

No due date set.

Dependencies

No dependencies set.

Reference: github/netbox#520