What are the main differences between asynchronous and synchronous server application architectures?

Synchronous architecture of server applications assumes that each request is processed sequentially: the server is blocked until the current operation completes. This is easy to implement, but with a large number of requests, it can lead to blocking and reduced performance.

Asynchronous architecture allows processing requests in a non-blocking manner: the server does not wait for the operation to complete, but continues to accept and process other requests. This increases scalability and efficiency when working with a large number of concurrent connections, especially during input-output operations.

Main differences:

• Synchronous: thread blocking until the operation completes, easier to implement.
• Asynchronous: non-blocking processing, requires event or callback management, better suited for high-load systems.

Example in Python using asyncio (asynchronous server):

import asyncio

async def handle_client(reader, writer):
    data = await reader.read(100)
    message = data.decode()
    writer.write(data)
    await writer.drain()
    writer.close()

async def main():
    server = await asyncio.start_server(handle_client, '127.0.0.1', 8888)
    async with server:
        await server.serve_forever()

asyncio.run(main())