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Tablestore:Product overview

Last Updated:Sep 03, 2026

Built on Tablestore, Memory Storage provides serverless memory writes, automatic extraction, and semantic retrieval for AI agents. It supports data isolation for millions of tenants and memory reuse across sessions.

What is Memory Storage

Memory Storage is a managed memory service built on Tablestore for AI agents. You write conversations or text to a memory store. The service retains original messages and extracts searchable long-term memories. In later conversations, the agent recalls relevant memories through natural language queries to produce more coherent, context-aware responses.

AI agents need to handle continuous conversations, cross-session preferences, user profiles, and historical facts. Relying only on the context window leads to higher token costs, lost history, and context interference. Building memory extraction, storage, and retrieval from scratch requires LLM calls, vector search, full-text search, data isolation, and auditing. Memory Storage packages these capabilities into a unified memory store interface. Integrate through an SDK, the CLI, or agent plugins without building the extraction and retrieval pipeline yourself.

To try Memory Storage, see Quick start.

Core benefits

Serverless and ready to use

Memory Storage uses a fully managed serverless architecture. Write and retrieve memories through APIs without deploying or maintaining infrastructure. Pay only for what you use, with no charges at zero usage.

Automatic memory extraction

After you write conversations or text, the service extracts key facts and preferences into structured memories. No custom extraction or organization logic is required. Use memory-store-level extraction instructions (extractInstructions) to focus extraction on business-critical information.

File view access

Service-managed structured memories support two read modes: structured access through SDKs, the CLI, and other interfaces, or directory- and file-based access through file views.

File views expose memory data as read-only files. Applications continue to write or update source memories through structured interfaces, preventing conflicts between file operations and structured memories.

File memory

If you already have Markdown or other UTF-8 text files, or want to organize a memory directory yourself, write the files directly to a file memory store. Applications control file paths and can create, read, update, rename, and delete files, as well as query file version history.

Automatic memory consolidation (Dream)

Memory consolidation (Dream) asynchronously refines stored memories in the background. It can merge, deduplicate, and update long-term memories (memory), and extract reusable skills (skill) and structured user profiles (profile) from interaction history. Dream can generate proposals for manual confirmation or automatically apply changes that meet a confidence threshold.

Horizontal scaling

Built on Tablestore's distributed architecture, Memory Storage scales horizontally. Storage capacity theoretically has no upper limit and can support millions of tenants and tens of billions of memories.

Accurate semantic retrieval

Memory Storage combines vector search and full-text search in a hybrid retrieval mode. Natural language queries recall relevant memories. Optionally enable Rerank, similarity threshold filtering (minSimilarity), and source evidence return (includeEvidence) to improve relevance and explainability.

Lower token costs

Compared with injecting full conversation histories, Memory Storage saves about 95% of tokens with almost no loss in response quality. Retrieving only relevant memories reduces unrelated context. It also avoids O(N²) cumulative token growth from repeatedly injecting the full history and the "Lost in the Middle" performance degradation.

Multi-tenant isolation

A four-level Scope of appId, tenantId, agentId, and runId isolates data by application, tenant, agent, and session for millions of tenants.

Comparison with mem0

The following table compares Memory Storage with the open-source memory system mem0.

Dimension

Memory Storage

Open-source mem0

Deployment and maintenance

Serverless, ready to use through APIs, with no infrastructure maintenance

Requires deployment and maintenance of the underlying components

Memory extraction

Automatic extraction with no extra development

Requires custom extraction logic

Retrieval accuracy

88.25% overall on LoCoMo, with strong performance in complex reasoning use cases

64.20% overall on LoCoMo

Retrieval latency

P95 ≤ 288 ms at the scale of hundreds of millions of entries

About four times the Tablestore latency at the same scale

Storage scale

Horizontal scaling, validated with 1.2 million tenants and more than 100 million memories

Limited by the underlying storage solution

Multi-tenant isolation

Built-in four-level Scope support

Requires a custom isolation scheme

For detailed benchmark data and methodology, see Architecture and technology selection.

Use cases

Continuity across multi-turn conversations

Write historical messages to a memory store during long conversations. The service retains the original messages and extracts key facts. Later conversations retrieve only relevant memories on demand, avoiding full-history context injection.

Preference reuse across sessions

User preferences, habits, and constraints expressed across sessions are extracted into long-term memories. New sessions retrieve these memories through semantic search, maintaining consistent agent responses across different times and entry points.

Knowledge sharing across multiple agents

Using a wildcard for agentId in the four-level Scope lets multiple agents share the same user memories within a tenant. This avoids extracting and maintaining the same facts for each agent.

User profile accumulation

Continuously write user behavior, attributes, and historical facts to a memory store. The service automatically consolidates the data into structured profile units that recommendation, customer service, and marketing agents can retrieve.

Access methods

Method

Use case

Documentation

Agent Storage SDK

Access structured memory and file memory with an API key. Use AccessKey credentials to call the full Tablestore API set or upload knowledge base documents.

Agent Storage SDK, File memory

Tablestore native SDK

Call structured memory APIs from business services with AccessKey credentials

Python SDK, Node.js SDK

CLI

Local debugging, operations, and automation scripts

CLI usage

Agent plugins

Integrate memory retrieval and write-back into existing agent frameworks

Agent ecosystem integration

Supported regions

Memory Storage is currently available only in the China (Beijing) and China (Hangzhou) regions.

References