Building Intelligent Memory Systems for Production AI Agents on AWS
Memory is what transforms a stateless AI model into an intelligent agent capable of learning, adapting, and maintaining context across interactions. In production environments, implementing robust memory systems requires careful orchestration of multiple AWS services, each optimized for specific memory patterns—from millisecond-latency working memory to petabyte-scale long-term storage.
Key Insight
The Four Pillars of Agent Memory Architecture
Production AI agents require four distinct memory types, each served by different AWS services optimized for specific access patterns. Working memory handles immediate context with sub-millisecond latency using ElastiCache Redis, typically storing the current conversation turn and active tool states.
47ms
Average memory retrieval latency for production agents at scale
This benchmark represents the combined latency of fetching working memory from ElastiCache, session state from DynamoDB, and relevant context from OpenSearch.
Framework
MARS: Memory Architecture for Reliable Systems
Mutability Classification
Categorize data by how frequently it changes. High-mutability data like current conversation state b...
Access Pattern Analysis
Map read/write ratios and latency requirements for each data type. Working memory sees 100:1 read:wr...
Retention Policy Design
Define TTLs and archival rules for each memory tier. Session memory typically expires after 24 hours...
Synchronization Strategy
Design how memories flow between tiers. Working memory should flush to short-term storage every conv...
N
Notion
Building Semantic Memory for AI Writing Assistants
The new architecture reduced AI response latency by 62% while improving relevanc...
Agent Memory Flow Architecture
User Request
ElastiCache (Working...
DynamoDB (Session St...
OpenSearch (Semantic...
DynamoDB vs. Traditional SQL for Agent State Management
DynamoDB
Single-digit millisecond latency at any scale with no perfor...
Automatic scaling handles traffic spikes without manual inte...
Pay-per-request pricing ideal for variable agent workloads
Built-in TTL automatically expires stale session data
PostgreSQL (RDS/Aurora)
Latency increases under load, requiring careful capacity pla...
Manual scaling with potential downtime during resize operati...
Fixed costs regardless of actual usage, expensive for bursty...
Requires scheduled jobs or triggers for data cleanup
Memory Isolation is Non-Negotiable for Multi-Tenant Agents
Every memory access must be scoped to the correct tenant, user, and session. A single bug that leaks one user's memories to another can destroy trust and create legal liability.
DynamoDB Table Design for Agent Session Memorytypescript
Vector Embeddings Are the Bridge Between Language and Memory
Vector embeddings transform text into numerical representations that capture semantic meaning, enabling agents to retrieve relevant memories even when the exact words differ. When a user asks about 'quarterly revenue,' a well-designed vector search can retrieve memories about 'Q3 earnings,' 'financial results,' or 'sales performance' because these concepts cluster together in embedding space.
Anti-Pattern: The Infinite Context Window Fallacy
❌ Problem
Costs explode as you pay for tokens the model largely ignores. Latency increases...
✓ Solution
Implement semantic retrieval that fetches only relevant memories for each query....
Implementing Your First Agent Memory System on AWS
1
Create the DynamoDB Session Table
2
Set Up OpenSearch Serverless Collection
3
Deploy ElastiCache Redis Cluster
4
Implement the Memory Service Layer
5
Build the Memory Retrieval Pipeline
Memory System Production Readiness Checklist
Key Insight
ElastiCache Redis: The Speed Layer Your Agents Need
ElastiCache Redis serves as the speed layer in your memory architecture, providing sub-millisecond access to frequently-used data. For agent systems, Redis excels at three critical functions: caching assembled context to avoid repeated DynamoDB and OpenSearch queries, storing working memory for multi-step tool execution, and maintaining rate limiting counters for API calls.
A
Anthropic
Scaling Claude's Memory for Enterprise Deployments
The redesigned system reduced memory-related latency by 73% and decreased storag...
Use DynamoDB Single-Table Design for Agent State
Rather than creating separate tables for sessions, messages, user preferences, and agent state, use a single-table design with carefully crafted partition and sort keys. This reduces the number of connections, simplifies transactions across entity types, and improves cost efficiency.
Practice Exercise
Build a Memory-Enabled Conversation Agent
45 min
Essential Resources for Agent Memory Implementation
AWS DynamoDB Developer Guide - Best Practices
article
OpenSearch Vector Search Tutorial
article
Redis University - RU101: Introduction to Redis Data Structures
video
LangChain Memory Documentation
article
Key Insight
S3: The Artifact Memory Layer for Generated Content
While DynamoDB and OpenSearch handle structured data and vectors, S3 serves as the artifact memory layer for large, unstructured content that agents generate or reference. This includes generated images, PDF reports, code files, audio transcriptions, and any content too large for database storage.
Framework
The Memory Tier Architecture Pattern
Hot Memory Layer (ElastiCache)
Sub-millisecond access for active conversation context, current task state, and frequently accessed ...
Warm Memory Layer (DynamoDB)
Single-digit millisecond access for session history, task queues, and structured metadata. This laye...
Semantic Memory Layer (OpenSearch)
Tens of milliseconds for vector similarity search, enabling agents to retrieve relevant past experie...
Cold Memory Layer (S3)
Hundreds of milliseconds for large artifacts, complete conversation archives, and audit trails. This...
DynamoDB On-Demand vs Provisioned Capacity for Agent Workloads
OpenSearch Serverless with vector engine support launched in 2023 and represents a paradigm shift for agent memory systems. Instead of managing cluster sizing, shard allocation, and capacity planning, you simply create a collection and start indexing vectors.
Implementing Semantic Memory with OpenSearch
1
Create OpenSearch Serverless Collection
2
Design Your Vector Index Schema
3
Implement Embedding Generation Pipeline
4
Build the Retrieval Interface
5
Configure Memory Lifecycle Management
Anti-Pattern: Storing Raw Conversation Text as Embeddings
❌ Problem
Retrieval quality degrades as the memory store grows. Agents retrieve irrelevant...
✓ Solution
Extract and embed semantic summaries rather than raw text. Before embedding, use...
I
Intercom
Fin AI's Multi-Tier Memory Architecture
Average memory retrieval time dropped from 340ms to 67ms. Customer satisfaction ...
ElastiCache Cluster Mode Disabled vs Enabled
For agent memory workloads, start with Cluster Mode Disabled unless you need more than 500GB of data or 500,000 operations per second. Cluster Mode Enabled adds complexity with hash slot management and cross-slot operation limitations that can break common agent patterns like MULTI/EXEC transactions across different keys.
Latency difference between ElastiCache and DynamoDB for hot data
ElastiCache delivers sub-millisecond response times (0.2-0.5ms) compared to DynamoDB's single-digit milliseconds (170-400ms for complex queries).
Framework
The Memory Consistency Model for Multi-Agent Systems
Strong Consistency (DynamoDB)
Use for state that must never conflict: task ownership, workflow status, financial transactions. Dyn...
Eventual Consistency (Default)
Acceptable for most agent memory: conversation history, cached tool results, user preferences. Reads...
Session Consistency (ElastiCache)
A single agent instance always sees its own writes immediately through cache locality. Different ins...
Causal Consistency (Event Sourcing)
Operations that depend on each other are seen in order, but independent operations may be reordered....
S3 Artifact Storage Best Practices
Complete Agent Memory Architecture on AWS
Agent Request
ElastiCache (Working...
DynamoDB (Session St...
↓
OpenSearch (Semantic...
S
Stripe
Stripe's Fraud Detection Agent Memory System
Decision latency dropped from 230ms to 47ms while fraud detection accuracy impro...
Practice Exercise
Build a Multi-Tier Memory System for a Customer Support Agent
90 min
Memory Encryption Requirements for Production
Enable encryption at rest for all memory tiers: DynamoDB (AWS-managed or CMK), ElastiCache (at-rest and in-transit encryption), OpenSearch (node-to-node encryption and encryption at rest), and S3 (SSE-S3 or SSE-KMS). For agents handling PII or sensitive data, use customer-managed KMS keys to maintain key rotation control and audit trails.
How you partition agent memory across storage systems determines your maximum scale. The naive approach—one DynamoDB partition per session—works until you have sessions with thousands of turns, hitting the 10GB partition limit.
Practice Exercise
Build a Complete Agent Memory System
90 min
Complete Memory Manager Implementationpython
123456789101112
import boto3
import json
import hashlib
from datetime import datetime, timedelta
from typing import Dict, List, Optional
from opensearchpy import OpenSearch, RequestsHttpConnection
import redis
class AgentMemoryManager:
def __init__(self, config: Dict):
self.dynamodb = boto3.resource('dynamodb')
self.s3 = boto3.client('s3')
Production Memory System Deployment Checklist
Anti-Pattern: The Monolithic Memory Store
❌ Problem
As the agent handles more conversations, scan operations become increasingly exp...
✓ Solution
Design a purpose-built architecture where each service handles what it does best...
Agents operate on stale context, leading to repetitive questions or contradictor...
✓ Solution
Implement a tiered TTL strategy based on data volatility—active conversation con...
Anti-Pattern: Over-Indexing Everything in OpenSearch
❌ Problem
OpenSearch costs grow 5-10x higher than necessary because storage and compute sc...
✓ Solution
Be selective about what gets indexed for semantic search. Only index memories wh...
Practice Exercise
Implement Memory Consolidation Pipeline
60 min
Practice Exercise
Build Multi-Region Memory Replication
75 min
Memory Importance Scoring and Consolidationpython
123456789101112
import boto3
from datetime import datetime, timedelta
from typing import List, Dict
import anthropic
class MemoryConsolidator:
def __init__(self, memory_manager, claude_client):
self.memory = memory_manager
self.claude = claude_client
def calculate_importance_score(self, memory: Dict) -> float:
"""Calculate memory importance based on multiple factors"""
Essential Resources for AWS Memory Implementation
AWS DynamoDB Best Practices Guide
article
OpenSearch k-NN Plugin Documentation
article
ElastiCache for Redis Best Practices
article
Building Serverless Applications with DynamoDB Streams
video
Monitor DynamoDB Consumed Capacity Closely
DynamoDB throttling can cascade into cache misses and increased load on other services. Set up CloudWatch alarms for consumed read/write capacity exceeding 80% of provisioned capacity, and enable auto-scaling with appropriate minimum and maximum bounds.
Use DynamoDB Streams for Real-Time Cache Invalidation
Instead of implementing complex cache invalidation logic in your application, use DynamoDB Streams to trigger Lambda functions that update or invalidate cache entries. This decouples your write path from cache management and ensures consistency even when writes come from multiple sources.
Framework
Memory System Health Metrics Framework
Cache Effectiveness Score
Composite metric combining cache hit rate (target >85%), cache latency (target <5ms p99), and evicti...
Memory Retrieval Quality
Measures semantic search relevance through user feedback signals and retrieval-augmented generation ...
Storage Efficiency Ratio
Ratio of active memories to total stored memories, accounting for consolidation and archival. Target...
Cross-Service Latency Budget
End-to-end latency breakdown across cache lookup, DynamoDB query, OpenSearch search, and S3 retrieva...
99.99%
DynamoDB availability SLA for global tables
DynamoDB global tables provide the highest availability SLA of any AWS database service, making them ideal for critical agent state.
Plan for Memory Migration from Day One
Your memory schema will evolve as agent capabilities expand. Design your DynamoDB schema with version fields and implement backward-compatible readers that handle multiple schema versions.
N
Notion
Building AI Memory for Millions of Workspaces
The architecture supports over 30 million workspaces with AI memory capabilities...
Practice Exercise
Implement Memory Access Audit Trail
45 min
Complete Memory System Data Flow
Agent Request
API Gateway
Lambda Handler
ElastiCache Check
Chapter Complete!
DynamoDB serves as the foundation for agent memory, providin...
OpenSearch enables semantic memory retrieval through vector ...
ElastiCache dramatically reduces latency and cost by caching...
S3 provides cost-effective storage for large artifacts like ...
Next: Begin by implementing a basic memory system using DynamoDB for state and ElastiCache for caching