0Pricing
AI Agents with LangChain & Autonomous Workflows · 课时

异步执行智能体

学习为智能体实现异步模式，使其能够并行执行任务并提高响应速度

异步执行智能体 是 CoddyKit 上的免费 AI Agents with LangChain & Autonomous Workflows 课时。 这是第 2 节课，共 4 节。 你可以在下方免费阅读本课时的完整内容 — 然后在浏览器中使用内置代码编辑器和全天候 AI 导师进行实践。 这是 AI Agents with LangChain & Autonomous Workflows 学习路径的一部分，你的进度在网页和 CoddyKit 应用中同步。 AI Agents with LangChain & Autonomous Workflows 课程共包含 4 节课。

本课时的部分内容尚未翻译，以英文显示。

Why Asynchronous Agents?

Imagine your AI agent needs to do several things at once: fetch data from two APIs, analyze text with an LLM, and then store a result. If it does these synchronously (one after another), it waits for each step to complete before starting the next.

This waiting can make your agent slow and unresponsive, especially when dealing with network calls or complex computations.

Synchronous vs. Asynchronous

Synchronous execution is like a single-lane road: only one car can pass at a time. If a car breaks down, all traffic stops.

  • Synchronous: Tasks run one by one.
  • Asynchronous: Tasks can start, pause while waiting for something (like an API response), and let other tasks run in the meantime. It's like a multi-lane highway or juggling multiple balls.

Asynchronous programming helps agents utilize idle time more effectively.

Python's Async/Await Keywords

Python uses the async and await keywords to enable asynchronous programming. Think of them as signals:

  • async def: Defines a function (called a coroutine) that can run asynchronously.
  • await: Pauses the current coroutine until the awaited task is complete, allowing other tasks to run.

Let's see a basic example:

import asyncio

async def say_hello():
    print("Hello ")
    await asyncio.sleep(1) # Simulate a delay
    print("World!")

async def main():
    await say_hello()

if __name__ == "__main__":
    asyncio.run(main())

The asyncio Event Loop

Behind the scenes, Python's asyncio library manages how asynchronous tasks run. It uses an event loop.

  • The event loop constantly monitors tasks.
  • When an await statement pauses a task, the event loop switches to another ready task.
  • Once the awaited task is done, the event loop resumes the paused task.

This allows non-blocking operations, improving overall efficiency.

Async LLM Calls in LangChain

Many LangChain components, especially LLMs, offer asynchronous versions of their methods. For example, instead of .invoke(), you can often use .ainvoke() for an asynchronous call.

This is crucial for making your agent responsive when querying large language models, which can take time.

import asyncio
from langchain_openai import ChatOpenAI
from langchain_core.messages import HumanMessage

async def main():
    # Make sure you have your OpenAI API key set up
    llm = ChatOpenAI(model="gpt-3.5-turbo", temperature=0)
    
    # Using .ainvoke() for an asynchronous call
    response = await llm.ainvoke([HumanMessage(content="What is the capital of Canada?")])
    print(response.content)

if __name__ == "__main__":
    asyncio.run(main())

Running Multiple LLM Calls Concurrently

The real power of async shines when you need to make multiple LLM calls. You don't have to wait for each one to finish before starting the next.

Use asyncio.gather() to run several asynchronous tasks in parallel and collect their results.

import asyncio
from langchain_openai import ChatOpenAI
from langchain_core.messages import HumanMessage

async def main():
    llm = ChatOpenAI(model="gpt-3.5-turbo", temperature=0)
    
    # Create multiple asynchronous LLM invocation tasks
    task1 = llm.ainvoke([HumanMessage(content="Tell me a fact about the sun.")])
    task2 = llm.ainvoke([HumanMessage(content="Tell me a fact about the moon.")])
    task3 = llm.ainvoke([HumanMessage(content="Tell me a fact about Earth.")])
    
    # Run all tasks concurrently and wait for them to complete
    results = await asyncio.gather(task1, task2, task3)
    
    for i, res in enumerate(results):
        print(f"Result {i+1}: {res.content}\n")

if __name__ == "__main__":
    asyncio.run(main())

Asynchronous Tool Execution

Just like LLMs, your custom tools can also be asynchronous! If your tool performs I/O-bound operations (like fetching data from a database or an external API), making it asynchronous will significantly improve agent performance.

To create an async tool, implement the _arun method in your BaseTool subclass.

import asyncio
from langchain.tools import BaseTool

class AsyncWebSearchTool(BaseTool):
    name: str = "AsyncWebSearch"
    description: str = "Searches the web asynchronously for a query."

    async def _arun(self, query: str) -> str:
        # Simulate an asynchronous web search API call
        await asyncio.sleep(1.5) 
        return f"Results for '{query}': Found 5 articles."

    def _run(self, query: str) -> str:
        # Fallback for synchronous calls (optional but good practice)
        return f"Sync results for '{query}': Found 4 articles."

async def main():
    tool = AsyncWebSearchTool()
    result = await tool.arun("latest AI news")
    print(result)

if __name__ == "__main__":
    asyncio.run(main())

Building Async Chains & Agents

When you combine asynchronous LLMs and tools into chains or agents, LangChain automatically leverages their async capabilities. Most LangChain runnables and chains also provide an .ainvoke() method.

This means you can build entire asynchronous workflows, allowing your agent to process complex tasks involving multiple steps and external calls much faster.

import asyncio
from langchain_openai import ChatOpenAI
from langchain_core.prompts import ChatPromptTemplate
from langchain_core.runnables import RunnableSequence

async def main():
    llm = ChatOpenAI(model="gpt-3.5-turbo", temperature=0)
    prompt = ChatPromptTemplate.from_template("What is a unique fact about {animal}?")
    
    # Define a simple chain
    chain = prompt | llm
    
    # Invoke the chain asynchronously
    response = await chain.ainvoke({"animal": "platypus"})
    print(response.content)

if __name__ == "__main__":
    asyncio.run(main())

Quick Check: Async Benefits

Let's check your understanding of asynchronous execution.

Recap: Mastering Async Agents

Great job! You've learned the fundamentals of asynchronous execution in Python and how to apply it to your LangChain agents.

  • Asynchronous programming (async/await) allows agents to perform tasks concurrently instead of waiting for each one.
  • This significantly improves responsiveness and throughput for I/O-bound operations.
  • LangChain's LLMs, tools, and chains often provide asynchronous methods (e.g., .ainvoke(), .arun()) to leverage this power.

By integrating async patterns, you can build more efficient and high-performing autonomous workflows!

常见问题解答

「异步执行智能体」课时是免费的吗？

是的 — 「异步执行智能体」的完整文本可在网页上免费阅读。要进行交互式练习（内置代码编辑器和全天候 AI 导师）并解锁 AI Agents with LangChain & Autonomous Workflows 课程的其余内容，请升级到 CoddyKit PRO。 AI Agents with LangChain & Autonomous Workflows 课程共包含 4 节课。

「异步执行智能体」这节课中我会学到什么？

学习为智能体实现异步模式，使其能够并行执行任务并提高响应速度 你通过在浏览器中直接运行的动手代码来练习 AI Agents with LangChain & Autonomous Workflows，全天候 AI 导师会在你学习这节课的过程中回答你的问题。

学习 AI Agents with LangChain & Autonomous Workflows 需要有经验吗？

无需任何先前经验。CoddyKit 上的 AI Agents with LangChain & Autonomous Workflows 课程适合初学者到高级学习者，你可以从这里开始或从头开始，按照自己的节奏学习。 这是第 2 节课，共 4 节。

「异步执行智能体」课时需要多长时间？

大多数 CoddyKit 课程大约需要 5–10 分钟。每节课都很精短且互动，所以你能稳步进步，并在网页和应用中从离开的地方继续。

我能在这节 AI Agents with LangChain & Autonomous Workflows 课中编写并运行代码吗？

能。每节 AI Agents with LangChain & Autonomous Workflows 课都包含内置代码编辑器，你可以在浏览器中直接编写并运行真实代码，并获得即时 AI 反馈 — 无需本地设置。

此课程中的所有课时

  1. 设计复杂工作流
  2. 异步执行智能体
  3. 错误处理与韧性
  4. 人在回路中的审批
← 返回 AI Agents with LangChain & Autonomous Workflows