René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"[perf] Replace MessageToDict with optimized custom dict builder - 4x faster JSON serialization","articleBody":"## Current Behavior\nThe feature server's /get-online-features endpoint uses google.protobuf.json_format.MessageToDict to convert protobuf responses to JSON. MessageToDict is a generic converter designed for any protobuf type, but for the known GetOnlineFeaturesResponse structure, a type-specific converter is 4x faster.\n\n## Steps to reproduce\n\n- Deploy Feast feature server to Kubernetes\n- Call /get-online-features with 100 entities and 50 features\n- Profile the endpoint and isolate MessageToDict time\n- Observe ~12ms spent in MessageToDict (98% of serialization time)\n- Compare with proto binary serialization which takes only 0.1ms\n- Implement custom dict builder and observe 2.9ms (4x improvement)\n\n### Specifications\n\n- Feast version: 0.60.0\n- Python version: 3.11\n- Tested on: OpenShift/Kubernetes with Redis, PostgreSQL, DynamoDB\n\n### Benchmark Results\nTested with 100 entities, 50 features in-cluster:\n```\nCurrent (MessageToDict + orjson):  12.0ms\n- MessageToDict only:            11.8ms  (98% of time!)\n- orjson (dict→JSON):             0.2ms\n\nCustom dict builder + orjson:       2.9ms\n-  Custom builder:                 2.7ms\n-  orjson (dict→JSON):             0.2ms\n\nProto binary (for comparison):      0.1ms\n```\n\n#### Why MessageToDict is Slow\n- Reflection-based field discovery for ANY protobuf message\n- Dynamic type checking for each field\n- Generic handling of all value types (oneofs, repeated, maps)\n- CamelCase/snake_case conversion logic\n- For GetOnlineFeaturesResponse, we know the exact schema, so all this reflection is unnecessary.\n\n\n## Possible Solution\nAdd sdk/python/feast/feature_server_utils.py with a custom dict builder\n\nMetric | Before | After | Improvement\n-- | -- | -- | --\nSerialization (100 entities) | 12.0ms | 2.9ms | 4.1x faster\nSerialization (500 entities) | ~55ms | ~13ms | 4.2x faster\n","author":{"url":"https://github.com/abhijeet-dhumal","@type":"Person","name":"abhijeet-dhumal"},"datePublished":"2026-02-24T05:57:18.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":1},"url":"https://github.com/6013/feast/issues/6013"}