I got a notice from google that its embedding-001 model will be deprecated this month and to switch over to gemini-embedding-001 instead, which I’ve done. However, now I have a bunch of these errors in my Discourse log: Error ERROR: expected 768 dimensions, not 3072 querying embeddings for model Gemini embedding Backtrace activesupport-8.0.3/lib/active_support/broadcast_logger.rb:218:in `block in dispatch' activesupport-8.0.3/lib/active_support/broadcast_logger.rb:217:in `map' activesupport-8.0.3/lib/active_support/broadcast_logger.rb:217:in `dispatch' activesupport-8.0.3/lib/active_support/broadcast_logger.rb:129:in `error' /var/www/discourse/plugins/discourse-ai/lib/embeddings/schema.rb:279:in `rescue in symmetric_similarity_search' /var/www/discourse/plugins/discourse-ai/lib/embeddings/schema.rb:195:in `symmetric_similarity_search' /var/www/discourse/plugins/discourse-ai/lib/embeddings/semantic_related.rb:24:in `block in related_topic_ids_for' /var/www/discourse/lib/cache.rb:93:in `fetch' /var/www/discourse/plugins/discourse-ai/lib/embeddings/semantic_related.rb:21:in `related_topic_ids_for' /var/www/discourse/plugins/discourse-ai/lib/embeddings/semantic_topic_query.rb:17:in `block in list_semantic_related_topics' /var/www/discourse/lib/topic_query.rb:532:in `create_list' /var/www/discourse/plugins/discourse-ai/lib/embeddings/semantic_topic_query.rb:16:in `list_semantic_related_topics' /var/www/discourse/plugins/discourse-ai/lib/embeddings/entry_point.rb:23:in `block in inject_into' /var/www/discourse/lib/plugin/instance.rb:435:in `public_send' /var/www/discourse/lib/plugin/instance.rb:435:in `block (2 levels) in add_to_class' /var/www/discourse/plugins/discourse-ai/lib/embeddings/entry_point.rb:11:in `block in inject_into' /var/www/discourse/lib/discourse_plugin_registry.rb:299:in `apply_modifier' /var/www/discourse/lib/topic_view.rb:726:in `suggested_topics' /var/www/discourse/app/serializers/suggested_topics_mixin.rb:15:in `include_suggested_topics?' active_model_serializers-0.8.4/lib/active_model/serializer.rb:375:in `include?' (eval at active_model_serializers-0.8.4/lib/active_model/serializer.rb:467):7:in `_fast_attributes' active_model_serializers-0.8.4/lib/active_model/serializer.rb:456:in `attributes' active_model_serializers-0.8.4/lib/active_model/serializer.rb:480:in `_serializable_hash' active_model_serializers-0.8.4/lib/active_model/serializer.rb:359:in `serializable_hash' active_model_serializers-0.8.4/lib/active_model/serializer.rb:347:in `as_json' activesupport-8.0.3/lib/active_support/json/encoding.rb:41:in `encode' activesupport-8.0.3/lib/active_support/json/encoding.rb:41:in `encode' activesupport-8.0.3/lib/active_support/core_ext/object/json.rb:42:in `to_json' active_model_serializers-0.8.4/lib/active_model/serializer.rb:331:in `to_json' multi_json-1.17.0/lib/multi_json/adapters/oj.rb:59:in `dump' multi_json-1.17.0/lib/multi_json/adapters/oj.rb:59:in `dump' multi_json-1.17.0/lib/multi_json/adapter.rb:26:in `dump' multi_json-1.17.0/lib/multi_json.rb:128:in `dump' /var/www/discourse/app/controllers/application_controller.rb:511:in `render_json_dump' /var/www/discourse/app/controllers/topics_controller.rb:274:in `posts' actionpack-8.0.3/lib/action_controller/metal/basic_implicit_render.rb:8:in `send_action' actionpack-8.0.3/lib/abstract_controller/base.rb:215:in `process_action' actionpack-8.0.3/lib/action_controller/metal/rendering.rb:193:in `process_action' actionpack-8.0.3/lib/abstract_controller/callbacks.rb:261:in `block in process_action' activesupport-8.0.3/lib/active_support/callbacks.rb:120:in `block in run_callbacks' /var/www/discourse/app/controllers/application_controller.rb:432:in `block in with_resolved_locale' i18n-1.14.7/lib/i18n.rb:353:in `with_locale' /var/www/discourse/app/controllers/application_controller.rb:432:in `with_resolved_locale' activesupport-8.0.3/lib/active_support/callbacks.rb:129:in `block in run_callbacks' activesupport-8.0.3/lib/active_support/callbacks.rb:140:in `run_callbacks' actionpack-8.0.3/lib/abstract_controller/callbacks.rb:260:in `process_action' actionpack-8.0.3/lib/action_controller/metal/rescue.rb:27:in `process_action' actionpack-8.0.3/lib/action_controller/metal/instrumentation.rb:76:in `block in process_action' activesupport-8.0.3/lib/active_support/notifications.rb:210:in `block in instrument' activesupport-8.0.3/lib/active_support/notifications/instrumenter.rb:58:in `instrument' activesupport-8.0.3/lib/active_support/notifications.rb:210:in `instrument' actionpack-8.0.3/lib/action_controller/metal/instrumentation.rb:75:in `process_action' actionpack-8.0.3/lib/action_controller/metal/params_wrapper.rb:259:in `process_action' activerecord-8.0.3/lib/active_record/railties/controller_runtime.rb:39:in `process_action' actionpack-8.0.3/lib/abstract_controller/base.rb:152:in `process' actionview-8.0.3/lib/action_view/rendering.rb:40:in `process' rack-mini-profiler-4.0.1/lib/mini_profiler/profiling_methods.rb:90:in `block in profile_method' actionpack-8.0.3/lib/action_controller/metal.rb:252:in `dispatch' actionpack-8.0.3/lib/action_controller/metal.rb:335:in `dispatch' actionpack-8.0.3/lib/action_dispatch/routing/route_set.rb:67:in `dispatch' actionpack-8.0.3/lib/action_dispatch/routing/route_set.rb:50:in `serve' actionpack-8.0.3/lib/action_dispatch/journey/router.rb:53:in `block in serve' actionpack-8.0.3/lib/action_dispatch/journey/router.rb:133:in `block in find_routes' actionpack-8.0.3/lib/action_dispatch/journey/router.rb:126:in `each' actionpack-8.0.3/lib/action_dispatch/journey/router.rb:126:in `find_routes' actionpack-8.0.3/lib/action_dispatch/journey/router.rb:34:in `serve' actionpack-8.0.3/lib/action_dispatch/routing/route_set.rb:908:in `call' /var/www/discourse/lib/middleware/omniauth_bypass_middleware.rb:35:in `call' /var/www/discourse/lib/middleware/crawler_hooks.rb:11:in `call' rack-2.2.18/lib/rack/tempfile_reaper.rb:15:in `call' rack-2.2.18/lib/rack/conditional_get.rb:27:in `call' rack-2.2.18/lib/rack/head.rb:12:in `call' actionpack-8.0.3/lib/action_dispatch/http/permissions_policy.rb:38:in `call' /var/www/discourse/lib/content_security_policy/middleware.rb:12:in `call' /var/www/discourse/lib/middleware/anonymous_cache.rb:415:in `call' /var/www/discourse/lib/middleware/csp_script_nonce_injector.rb:12:in `call' /var/www/discourse/config/initializers/008-rack-cors.rb:14:in `call' rack-2.2.18/lib/rack/session/abstract/id.rb:266:in `context' rack-2.2.18/lib/rack/session/abstract/id.rb:260:in `call' actionpack-8.0.3/lib/action_dispatch/middleware/cookies.rb:706:in `call' actionpack-8.0.3/lib/action_dispatch/middleware/callbacks.rb:31:in `block in call' activesupport-8.0.3/lib/active_support/callbacks.rb:100:in `run_callbacks' actionpack-8.0.3/lib/action_dispatch/middleware/callbacks.rb:30:in `call' actionpack-8.0.3/lib/action_dispatch/middleware/debug_exceptions.rb:31:in `call' actionpack-8.0.3/lib/action_dispatch/middleware/show_exceptions.rb:32:in `call' logster-2.20.1/lib/logster/middleware/reporter.rb:40:in `call' /var/www/discourse/lib/middleware/default_headers.rb:13:in `call' railties-8.0.3/lib/rails/rack/logger.rb:41:in `call_app' railties-8.0.3/lib/rails/rack/logger.rb:29:in `call' /var/www/discourse/config/initializers/100-quiet_logger.rb:20:in `call' /var/www/discourse/config/initializers/100-silence_logger.rb:29:in `call' actionpack-8.0.3/lib/action_dispatch/middleware/request_id.rb:34:in `call' /var/www/discourse/lib/middleware/enforce_hostname.rb:23:in `call' rack-2.2.18/lib/rack/method_override.rb:24:in `call' actionpack-8.0.3/lib/action_dispatch/middleware/executor.rb:16:in `call' rack-2.2.18/lib/rack/sendfile.rb:110:in `call' rack-mini-profiler-4.0.1/lib/mini_profiler.rb:191:in `call' /var/www/discourse/lib/middleware/processing_request.rb:12:in `call' message_bus-4.4.1/lib/message_bus/rack/middleware.rb:60:in `call' /var/www/discourse/lib/middleware/request_tracker.rb:410:in `call' actionpack-8.0.3/lib/action_dispatch/middleware/remote_ip.rb:96:in `call' railties-8.0.3/lib/rails/engine.rb:535:in `call' railties-8.0.3/lib/rails/railtie.rb:226:in `public_send' railties-8.0.3/lib/rails/railtie.rb:226:in `method_missing' rack-2.2.18/lib/rack/urlmap.rb:74:in `block in call' rack-2.2.18/lib/rack/urlmap.rb:58:in `each' rack-2.2.18/lib/rack/urlmap.rb:58:in `call' unicorn-6.1.0/lib/unicorn/http_server.rb:634:in `process_client' unicorn-6.1.0/lib/unicorn/http_server.rb:739:in `worker_loop' unicorn-6.1.0/lib/unicorn/http_server.rb:547:in `spawn_missing_workers' unicorn-6.1.0/lib/unicorn/http_server.rb:143:in `start' unicorn-6.1.0/bin/unicorn:128:in ` ' /var/www/discourse/vendor/bundle/ruby/3.3.0/bin/unicorn:25:in `load' /var/www/discourse/vendor/bundle/ruby/3.3.0/bin/unicorn:25:in ` ' Env HTTP HOSTS: discourse.spacecityweather.com``` It looks like the gemini-embedding-001 model returns 3072-dimension vectors unless it receives an output_dimensionality parameter in the request JSON payload, and although “768” is specified in my Discourse embedding config, either the parameter isn’t being sent or it isn’t being recognized. I could switch providers, but I have Google Cloud credits that I’d prefer to use, so I would prefer to stick wtih gemini for embeddings. What is the fix here? Do I need to wait on a Discourse patch, or am I safe to just configure a new embedding setup wtih gemini that uses 3072-dimension vectors?

[image] Lee_Ars: am I safe to just configure a new embedding setup wtih gemini that uses 3072-dimension vectors? This! Since we use Binary and Scalar Embedding Quantization for Significantly Faster & Cheaper Retrieval for our vector indexing, using vector with large dimensions is supported and welcome. You should always configure the Embeddings with their native dimensionality, unless you check the matryoshka_dimensions option.

Gotcha! I will run with 3072-dimension embeddings and stop caring. After having created a new embedding config and tested it, do I need to go into the rails console and nuke my existing embeddings and regenerate, or should I just leave Discourse alone and let it do its thing?

Gemini embedding setting not passing output_dimensionality?

Product Support

Falco (Falco) October 8, 2025, 2:38pm 5

After you delete the old embeddings configuration we will eventually clean the database up in a background task.

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Gemini embedding setting not passing output_dimensionality?

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