Engineering Logs for Troubleshooting & Debugging
Problem Description A production inference server that runs a Retrieval‑Augmented Generation (RAG) pipeline with TensorRT started throwing runtime errors after the passage encoder checkpoint was upgraded. The server processes thousands of queries per second in batches of up to 128 on a single GPU. Within seconds of deployment the following errors appeared in the logs: … Read more
Problem Description During a rolling update of a production Meta LLaMA RAG service, the retrieval‑augmented generation pipeline intermittently fails to retrieve embeddings. The failure manifests as: grpc deadline exceeded: context deadline exceeded while attempting to query vector store VectorStoreError: connection refused – unable to establish TCP connection to Faiss endpoint TimeoutError: failed to retrieve embeddings … Read more
Problem – Nightly RAG Batch Jobs Abort with Unsubstituted Prompt Placeholders The nightly batch pipeline that drives large‑scale Retrieval‑Augmented Generation (RAG) for reporting is failing. Each run aborts with a non‑zero exit code and the generated CSV contains malformed or empty fields. The primary symptom is a rendering error where template variables such as {{user_query}}, … Read more
TGI checkpoint storage class not found after A/B deployment Problem During an A/B testing rollout of Text Generation Inference (TGI) instances, the newly created replica fails to start and logs an error similar to: Failed to load checkpoint: storage class “fast-ssd” not found Other observed symptoms include: Pod tgi-a-12345 stays in Pending state. kubectl describe … Read more
Problem The RAG (Retrieval‑Augmented Generation) pipeline in the Qwen service started returning incomplete answers after the embedding model was upgraded from text‑embedding‑ada‑002 to qwen‑embedding‑v2. The most visible symptom was that the query decomposition stage produced either malformed sub‑queries or no sub‑queries at all, causing downstream vector search to return empty result sets. The issue manifested … Read more
RAG Pipeline Chunk Overlap Causing Duplicate Context Injection in Kubernetes Problem The Retrieval‑Augmented Generation (RAG) service deployed on a GPU‑accelerated Kubernetes cluster began exhibiting: Excessive token duplication in the vector store, leading to inflated embedding counts. Memory pressure on A100/H100 pods, resulting in OOMKilled restarts. Embedding latency spikes (>30 s) and a 40 % drop in retrieval … Read more
Problem – Pinecone Upsert Failures After RAG Model Update In a production RAG pipeline the ingestion workers generate embeddings with a new model (e.g., sentence‑transformers/all‑miniLM‑L6‑v2, 384‑dim) while the query service still uses the previous model (e.g., text‑ada‑002, 1536‑dim). The asynchronous, event‑driven architecture (AWS SQS → Lambda → Pinecone) allows the two services to scale independently, … Read more
Problem: RAG pipeline context injection failure after MLflow model update During a blue‑green deployment, traffic was shifted from the green version of the rag-service endpoint to the newly promoted blue version. After the switch, the Retrieval‑Augmented Generation (RAG) pipeline began sending prompts to the LLM that contained an empty or malformed context variable. Typical symptoms … Read more
Problem – Silent Retrieval Failures After Embedding Model Update The Retrieval‑Augmented Generation (RAG) pipeline started returning empty result sets while query latency dropped dramatically. No HTTP error was propagated to callers, and the existing Prometheus alerts did not fire. The symptoms appeared during a rolling deployment of a new sentence‑transformer model that changed the embedding … Read more
Problem – Empty Retrieval Results After Metadata Filter Update In a hybrid‑cloud RAG (Retrieval‑Augmented Generation) deployment, the vector store retrieval pipeline began returning empty result sets and occasional query timeouts after a new metadata filter was added. The failure manifested across on‑premises and cloud‑based retrieval nodes that synchronize Pinecone/Elasticsearch indexes. Typical log excerpt: 2024-07-15T10:42:03.112Z ERROR … Read more