CWLog - actor 개발 & 해킹 좋아하는 사람의 블로그 Zola 2025-05-26T00:00:00+00:00 https://blog.devcw.xyz/tags/actor/atom.xml 액터 모델 2025-05-26T00:00:00+00:00 2025-05-26T00:00:00+00:00 Unknown https://blog.devcw.xyz/posts/actor-model/ <h2 id="aegteo-model">액터 모델<a class="anchor" aria-hidden="true" href="#aegteo-model" hidden="">#</a> </h2> <p>1973년 Carl Hewitt가 처음 제안한 모델로, 분산 시스템과 동시성 프로그래밍의 복잡성을 해결하기 위해 고안되었다.</p> <p>액터 모델은 프로세스 간 통신을 추상화하여 동시성 프로그래밍을 단순화하는 모델이다.</p> <p><code>모든 것은 actor다</code> 라는 철학을 바탕으로 나왔으며, <code>actor</code>마다 내부적으로 메시지를 주고받는 방식으로 동작한다. 메시지를 주고받는 방식으로 동작하기 때문에 메시지 큐를 사용하는 방식과 유사하다.</p> <p>하나씩 톺아보자.</p> <h3 id="haegsim-weonri">핵심 원리<a class="anchor" aria-hidden="true" href="#haegsim-weonri" hidden="">#</a> </h3> <p>액터 모델의 기본 아이디어는 다음과 같다:</p> <ul> <li><strong>액터(Actor)</strong>: 계산의 기본 단위로, 각자 독립된 상태와 행동을 가진다</li> <li><strong>메시지 전달</strong>: 액터 간의 유일한 통신 수단으로, 비동기적으로 이루어진다</li> <li><strong>불변성</strong>: 메시지는 불변이며, 액터의 상태는 외부에서 직접 접근할 수 없다</li> </ul> <h3 id="teugjing">특징<a class="anchor" aria-hidden="true" href="#teugjing" hidden="">#</a> </h3> <ul> <li><strong>상태 캡슐화</strong>: 각 actor는 자신의 상태를 캡슐화하고 있으며, 외부에서 직접 접근할 수 없다.</li> <li><strong>메시지 기반 통신</strong>: actor는 메시지를 통해서만 서로 통신한다.</li> <li><strong>위치 투명성</strong>: actor는 로컬 또는 원격 위치를 구분하지 않고 메시지를 주고받는다.</li> <li><strong>비동기 처리</strong>: 메시지 전송은 논블로킹이며, 응답을 기다리지 않는다.</li> <li><strong>독립적 실행</strong>: 각 actor는 독립적으로 실행되며, 다른 actor의 실행에 영향을 받지 않는다.</li> </ul> <h3 id="aegteoyi-haengdong">액터의 행동<a class="anchor" aria-hidden="true" href="#aegteoyi-haengdong" hidden="">#</a> </h3> <p>액터가 메시지를 받았을 때 할 수 있는 일은 다음 세 가지뿐이다:</p> <ol> <li><strong>새로운 액터 생성</strong>: 다른 액터를 생성할 수 있다</li> <li><strong>메시지 전송</strong>: 다른 액터에게 메시지를 보낼 수 있다</li> <li><strong>상태 변경</strong>: 다음 메시지를 위해 자신의 상태를 변경할 수 있다</li> </ol> <h3 id="jangjeom">장점<a class="anchor" aria-hidden="true" href="#jangjeom" hidden="">#</a> </h3> <ul> <li><strong>데드락 방지</strong>: 공유 상태가 없어 데드락이 발생하지 않는다</li> <li><strong>확장성</strong>: 액터 수를 쉽게 늘려 시스템을 확장할 수 있다</li> <li><strong>오류 격리</strong>: 한 액터의 실패가 다른 액터에 영향을 주지 않는다</li> <li><strong>분산 처리</strong>: 네트워크를 통해 분산된 액터들이 투명하게 통신할 수 있다</li> <li><strong>테스트 용이성</strong>: 각 액터를 독립적으로 테스트할 수 있다</li> </ul> <h3 id="danjeom">단점<a class="anchor" aria-hidden="true" href="#danjeom" hidden="">#</a> </h3> <ul> <li><strong>디버깅 어려움</strong>: 비동기 메시지 전달로 인해 콜스택 추적이 어렵다</li> <li><strong>메시지 순서</strong>: 메시지 전달 순서가 보장되지 않을 수 있다</li> <li><strong>메모리 오버헤드</strong>: 각 액터마다 메일박스를 유지해야 한다</li> </ul> <h3 id="silje-sayong-sarye">실제 사용 사례<a class="anchor" aria-hidden="true" href="#silje-sayong-sarye" hidden="">#</a> </h3> <ul> <li><strong>Erlang/OTP</strong>: 통신 시스템에서 수백만 개의 액터를 동시에 실행</li> <li><strong>Akka</strong>: 대용량 트래픽을 처리하는 웹 서비스 (LinkedIn, Twitter 등)</li> <li><strong>Orleans</strong>: Microsoft의 분산 게임 서버 플랫폼</li> <li><strong>CAF</strong>: C++ 액터 프레임워크로 고성능 시스템 구축</li> </ul> <hr /> <p>사실 설명만 들으면 직접적으로 와닿지 않는다. 결국 최상위 추상화 레벨에서의 설명이기 때문이다. 실제로 구현해보면 그렇게 어렵지는 않다.</p> <p>또한, 뮤텍스를 안쓴다고는 하는데, 내부 구현에서는 뮤텍스를 사용한다 ㅋㅋ</p> <p>단순히 락의 책임이 개발자에서 액터 모델로 넘어간 거 뿐이다.</p> <p>그리고 구현할 때 애플리케이션 레이어에서 구현할텐데, 실제로는 이런식으로 쓰이는 디자인보다는 실제 노드 자체를 액터로 취급하고 노드 간 통신을 액터로 취급하는 경우가 더 많다. 그러니까, 분산 시스템에서 더 많이 채택되는 디자인이다.</p> <p>우선 구현해보기 전 사진부터 보자. <img src="https://labviewwiki.org/w/images/f/f7/Actor_Framework_Communication.png" alt="actor_model" /></p> <h3 id="rustro-guhyeonhan-aegteo-model">Rust로 구현한 액터 모델<a class="anchor" aria-hidden="true" href="#rustro-guhyeonhan-aegteo-model" hidden="">#</a> </h3> <pre class="giallo" style="color-scheme: light dark; color: light-dark(#24292E, #E1E4E8); background-color: light-dark(#FFFFFF, #24292E);"><code data-lang="rust"><span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);">use</span><span style="color: light-dark(#6F42C1, #B392F0);"> std</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">sync</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">mpsc</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span>{</span><span style="color: light-dark(#005CC5, #79B8FF);">self</span><span>,</span><span style="color: light-dark(#6F42C1, #B392F0);"> Receiver</span><span>,</span><span style="color: light-dark(#6F42C1, #B392F0);"> Sender</span><span>}</span><span>;</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);">use</span><span style="color: light-dark(#6F42C1, #B392F0);"> std</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span>thread</span><span>;</span></span> <span class="giallo-l"></span> <span class="giallo-l"><span>#</span><span>[</span><span>derive</span><span>(</span><span style="color: light-dark(#6F42C1, #B392F0);">Debug</span><span>)</span><span>]</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);">enum</span><span style="color: light-dark(#6F42C1, #B392F0);"> CalculatorMessage</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#6F42C1, #B392F0);"> Add</span><span> {</span><span> a</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> f64</span><span>,</span><span> b</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> f64</span><span>,</span><span> reply</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> Sender</span><span>&lt;</span><span style="color: light-dark(#6F42C1, #B392F0);">f64</span><span>&gt;</span><span> }</span><span>,</span></span> <span class="giallo-l"><span style="color: light-dark(#6F42C1, #B392F0);"> Multiply</span><span> {</span><span> a</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> f64</span><span>,</span><span> b</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> f64</span><span>,</span><span> reply</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> Sender</span><span>&lt;</span><span style="color: light-dark(#6F42C1, #B392F0);">f64</span><span>&gt;</span><span> }</span><span>,</span></span> <span class="giallo-l"><span style="color: light-dark(#6F42C1, #B392F0);"> Divide</span><span> {</span><span> a</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> f64</span><span>,</span><span> b</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> f64</span><span>,</span><span> reply</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> Sender</span><span>&lt;</span><span style="color: light-dark(#6F42C1, #B392F0);">Result</span><span>&lt;</span><span style="color: light-dark(#6F42C1, #B392F0);">f64</span><span>,</span><span style="color: light-dark(#6F42C1, #B392F0);"> String</span><span>&gt;</span><span>&gt;</span><span> }</span><span>,</span></span> <span class="giallo-l"><span style="color: light-dark(#6F42C1, #B392F0);"> GetHistory</span><span> {</span><span> reply</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> Sender</span><span>&lt;</span><span style="color: light-dark(#6F42C1, #B392F0);">Vec</span><span>&lt;</span><span style="color: light-dark(#6F42C1, #B392F0);">String</span><span>&gt;</span><span>&gt;</span><span> }</span><span>,</span></span> <span class="giallo-l"><span style="color: light-dark(#6F42C1, #B392F0);"> Clear</span><span>,</span></span> <span class="giallo-l"><span style="color: light-dark(#6F42C1, #B392F0);"> Stop</span><span>,</span></span> <span class="giallo-l"><span>}</span></span> <span class="giallo-l"></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);">struct</span><span style="color: light-dark(#6F42C1, #B392F0);"> CalculatorActor</span><span> {</span></span> <span class="giallo-l"><span> receiver</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> Receiver</span><span>&lt;</span><span style="color: light-dark(#6F42C1, #B392F0);">CalculatorMessage</span><span>&gt;</span><span>,</span></span> <span class="giallo-l"><span> history</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> Vec</span><span>&lt;</span><span style="color: light-dark(#6F42C1, #B392F0);">String</span><span>&gt;</span><span>,</span></span> <span class="giallo-l"><span>}</span></span> <span class="giallo-l"></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);">impl</span><span style="color: light-dark(#6F42C1, #B392F0);"> CalculatorActor</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> fn</span><span style="color: light-dark(#6F42C1, #B392F0);"> new</span><span>(</span><span>receiver</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> Receiver</span><span>&lt;</span><span style="color: light-dark(#6F42C1, #B392F0);">CalculatorMessage</span><span>&gt;</span><span>)</span><span style="color: light-dark(#D73A49, #F97583);"> -&gt;</span><span style="color: light-dark(#005CC5, #79B8FF);"> Self</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#6F42C1, #B392F0);"> CalculatorActor</span><span> {</span></span> <span class="giallo-l"><span> receiver</span><span>,</span></span> <span class="giallo-l"><span> history</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> Vec</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">new</span><span>(</span><span>)</span><span>,</span></span> <span class="giallo-l"><span> }</span></span> <span class="giallo-l"><span> }</span></span> <span class="giallo-l"></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> fn</span><span style="color: light-dark(#6F42C1, #B392F0);"> run</span><span>(</span><span style="color: light-dark(#D73A49, #F97583);">&amp;</span><span style="color: light-dark(#D73A49, #F97583);">mut</span><span style="color: light-dark(#005CC5, #79B8FF);"> self</span><span>)</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> while</span><span style="color: light-dark(#D73A49, #F97583);"> let</span><span style="color: light-dark(#6F42C1, #B392F0);"> Ok</span><span>(</span><span>message</span><span>)</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span style="color: light-dark(#005CC5, #79B8FF);"> self</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span>receiver</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">recv</span><span>(</span><span>)</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> match</span><span> message</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#6F42C1, #B392F0);"> CalculatorMessage</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">Add</span><span> {</span><span> a</span><span>,</span><span> b</span><span>,</span><span> reply</span><span> }</span><span style="color: light-dark(#D73A49, #F97583);"> =&gt;</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span> result</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span> a</span><span style="color: light-dark(#D73A49, #F97583);"> +</span><span> b</span><span>;</span></span> <span class="giallo-l"><span style="color: light-dark(#005CC5, #79B8FF);"> self</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span>history</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">push</span><span>(</span><span style="color: light-dark(#6F42C1, #B392F0);">format!</span><span>(</span><span style="color: light-dark(#032F62, #9ECBFF);">&quot;</span><span style="color: light-dark(#032F62, #9ECBFF);">{</span><span style="color: light-dark(#032F62, #9ECBFF);">}</span><span style="color: light-dark(#032F62, #9ECBFF);"> + </span><span style="color: light-dark(#032F62, #9ECBFF);">{</span><span style="color: light-dark(#032F62, #9ECBFF);">}</span><span style="color: light-dark(#032F62, #9ECBFF);"> = </span><span style="color: light-dark(#032F62, #9ECBFF);">{</span><span style="color: light-dark(#032F62, #9ECBFF);">}</span><span style="color: light-dark(#032F62, #9ECBFF);">&quot;</span><span>,</span><span> a</span><span>,</span><span> b</span><span>,</span><span> result</span><span>)</span><span>)</span><span>;</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span> _</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span> reply</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">send</span><span>(</span><span>result</span><span>)</span><span>;</span></span> <span class="giallo-l"><span> }</span></span> <span class="giallo-l"><span style="color: light-dark(#6F42C1, #B392F0);"> CalculatorMessage</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">Multiply</span><span> {</span><span> a</span><span>,</span><span> b</span><span>,</span><span> reply</span><span> }</span><span style="color: light-dark(#D73A49, #F97583);"> =&gt;</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span> result</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span> a</span><span style="color: light-dark(#D73A49, #F97583);"> *</span><span> b</span><span>;</span></span> <span class="giallo-l"><span style="color: light-dark(#005CC5, #79B8FF);"> self</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span>history</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">push</span><span>(</span><span style="color: light-dark(#6F42C1, #B392F0);">format!</span><span>(</span><span style="color: light-dark(#032F62, #9ECBFF);">&quot;</span><span style="color: light-dark(#032F62, #9ECBFF);">{</span><span style="color: light-dark(#032F62, #9ECBFF);">}</span><span style="color: light-dark(#032F62, #9ECBFF);"> * </span><span style="color: light-dark(#032F62, #9ECBFF);">{</span><span style="color: light-dark(#032F62, #9ECBFF);">}</span><span style="color: light-dark(#032F62, #9ECBFF);"> = </span><span style="color: light-dark(#032F62, #9ECBFF);">{</span><span style="color: light-dark(#032F62, #9ECBFF);">}</span><span style="color: light-dark(#032F62, #9ECBFF);">&quot;</span><span>,</span><span> a</span><span>,</span><span> b</span><span>,</span><span> result</span><span>)</span><span>)</span><span>;</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span> _</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span> reply</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">send</span><span>(</span><span>result</span><span>)</span><span>;</span></span> <span class="giallo-l"><span> }</span></span> <span class="giallo-l"><span style="color: light-dark(#6F42C1, #B392F0);"> CalculatorMessage</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">Divide</span><span> {</span><span> a</span><span>,</span><span> b</span><span>,</span><span> reply</span><span> }</span><span style="color: light-dark(#D73A49, #F97583);"> =&gt;</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> if</span><span> b</span><span style="color: light-dark(#D73A49, #F97583);"> ==</span><span style="color: light-dark(#005CC5, #79B8FF);"> 0</span><span style="color: light-dark(#005CC5, #79B8FF);">.</span><span style="color: light-dark(#005CC5, #79B8FF);">0</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span> _</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span> reply</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">send</span><span>(</span><span style="color: light-dark(#6F42C1, #B392F0);">Err</span><span>(</span><span style="color: light-dark(#032F62, #9ECBFF);">&quot;</span><span style="color: light-dark(#032F62, #9ECBFF);">Division by zero</span><span style="color: light-dark(#032F62, #9ECBFF);">&quot;</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">to_string</span><span>(</span><span>)</span><span>)</span><span>)</span><span>;</span></span> <span class="giallo-l"><span> }</span><span style="color: light-dark(#D73A49, #F97583);"> else</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span> result</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span> a</span><span style="color: light-dark(#D73A49, #F97583);"> /</span><span> b</span><span>;</span></span> <span class="giallo-l"><span style="color: light-dark(#005CC5, #79B8FF);"> self</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span>history</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">push</span><span>(</span><span style="color: light-dark(#6F42C1, #B392F0);">format!</span><span>(</span><span style="color: light-dark(#032F62, #9ECBFF);">&quot;</span><span style="color: light-dark(#032F62, #9ECBFF);">{</span><span style="color: light-dark(#032F62, #9ECBFF);">}</span><span style="color: light-dark(#032F62, #9ECBFF);"> / </span><span style="color: light-dark(#032F62, #9ECBFF);">{</span><span style="color: light-dark(#032F62, #9ECBFF);">}</span><span style="color: light-dark(#032F62, #9ECBFF);"> = </span><span style="color: light-dark(#032F62, #9ECBFF);">{</span><span style="color: light-dark(#032F62, #9ECBFF);">}</span><span style="color: light-dark(#032F62, #9ECBFF);">&quot;</span><span>,</span><span> a</span><span>,</span><span> b</span><span>,</span><span> result</span><span>)</span><span>)</span><span>;</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span> _</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span> reply</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">send</span><span>(</span><span style="color: light-dark(#6F42C1, #B392F0);">Ok</span><span>(</span><span>result</span><span>)</span><span>)</span><span>;</span></span> <span class="giallo-l"><span> }</span></span> <span class="giallo-l"><span> }</span></span> <span class="giallo-l"><span style="color: light-dark(#6F42C1, #B392F0);"> CalculatorMessage</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">GetHistory</span><span> {</span><span> reply</span><span> }</span><span style="color: light-dark(#D73A49, #F97583);"> =&gt;</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span> _</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span> reply</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">send</span><span>(</span><span style="color: light-dark(#005CC5, #79B8FF);">self</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span>history</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">clone</span><span>(</span><span>)</span><span>)</span><span>;</span></span> <span class="giallo-l"><span> }</span></span> <span class="giallo-l"><span style="color: light-dark(#6F42C1, #B392F0);"> CalculatorMessage</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">Clear</span><span style="color: light-dark(#D73A49, #F97583);"> =&gt;</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#005CC5, #79B8FF);"> self</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span>history</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">clear</span><span>(</span><span>)</span><span>;</span></span> <span class="giallo-l"><span style="color: light-dark(#6F42C1, #B392F0);"> println!</span><span>(</span><span style="color: light-dark(#032F62, #9ECBFF);">&quot;</span><span style="color: light-dark(#032F62, #9ECBFF);">History cleared</span><span style="color: light-dark(#032F62, #9ECBFF);">&quot;</span><span>)</span><span>;</span></span> <span class="giallo-l"><span> }</span></span> <span class="giallo-l"><span style="color: light-dark(#6F42C1, #B392F0);"> CalculatorMessage</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">Stop</span><span style="color: light-dark(#D73A49, #F97583);"> =&gt;</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#6F42C1, #B392F0);"> println!</span><span>(</span><span style="color: light-dark(#032F62, #9ECBFF);">&quot;</span><span style="color: light-dark(#032F62, #9ECBFF);">Calculator stopping...</span><span style="color: light-dark(#032F62, #9ECBFF);">&quot;</span><span>)</span><span>;</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> break</span><span>;</span></span> <span class="giallo-l"><span> }</span></span> <span class="giallo-l"><span> }</span></span> <span class="giallo-l"><span> }</span></span> <span class="giallo-l"><span> }</span></span> <span class="giallo-l"><span>}</span></span> <span class="giallo-l"></span> <span class="giallo-l"><span>#</span><span>[</span><span>derive</span><span>(</span><span style="color: light-dark(#6F42C1, #B392F0);">Clone</span><span>)</span><span>]</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);">struct</span><span style="color: light-dark(#6F42C1, #B392F0);"> CalculatorHandle</span><span> {</span></span> <span class="giallo-l"><span> sender</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> Sender</span><span>&lt;</span><span style="color: light-dark(#6F42C1, #B392F0);">CalculatorMessage</span><span>&gt;</span><span>,</span></span> <span class="giallo-l"><span>}</span></span> <span class="giallo-l"></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);">impl</span><span style="color: light-dark(#6F42C1, #B392F0);"> CalculatorHandle</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> fn</span><span style="color: light-dark(#6F42C1, #B392F0);"> new</span><span>(</span><span>)</span><span style="color: light-dark(#D73A49, #F97583);"> -&gt;</span><span style="color: light-dark(#005CC5, #79B8FF);"> Self</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span> (</span><span>sender</span><span>,</span><span> receiver</span><span>)</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span style="color: light-dark(#6F42C1, #B392F0);"> mpsc</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">channel</span><span>(</span><span>)</span><span>;</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span style="color: light-dark(#D73A49, #F97583);"> mut</span><span> actor</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span style="color: light-dark(#6F42C1, #B392F0);"> CalculatorActor</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">new</span><span>(</span><span>receiver</span><span>)</span><span>;</span></span> <span class="giallo-l"></span> <span class="giallo-l"><span style="color: light-dark(#6F42C1, #B392F0);"> thread</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">spawn</span><span>(</span><span style="color: light-dark(#D73A49, #F97583);">move</span><span style="color: light-dark(#D73A49, #F97583);"> |</span><span style="color: light-dark(#D73A49, #F97583);">|</span><span> {</span></span> <span class="giallo-l"><span> actor</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">run</span><span>(</span><span>)</span><span>;</span></span> <span class="giallo-l"><span> }</span><span>)</span><span>;</span></span> <span class="giallo-l"></span> <span class="giallo-l"><span style="color: light-dark(#6F42C1, #B392F0);"> CalculatorHandle</span><span> {</span><span> sender</span><span> }</span></span> <span class="giallo-l"><span> }</span></span> <span class="giallo-l"></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> fn</span><span style="color: light-dark(#6F42C1, #B392F0);"> add</span><span>(</span><span style="color: light-dark(#D73A49, #F97583);">&amp;</span><span style="color: light-dark(#005CC5, #79B8FF);">self</span><span>,</span><span> a</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> f64</span><span>,</span><span> b</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> f64</span><span>)</span><span style="color: light-dark(#D73A49, #F97583);"> -&gt;</span><span style="color: light-dark(#6F42C1, #B392F0);"> f64</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span> (</span><span>reply_sender</span><span>,</span><span> reply_receiver</span><span>)</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span style="color: light-dark(#6F42C1, #B392F0);"> mpsc</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">channel</span><span>(</span><span>)</span><span>;</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span> _</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span style="color: light-dark(#005CC5, #79B8FF);"> self</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span>sender</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">send</span><span>(</span><span style="color: light-dark(#6F42C1, #B392F0);">CalculatorMessage</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">Add</span><span> {</span><span> a</span><span>,</span><span> b</span><span>,</span><span> reply</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span> reply_sender</span><span> }</span><span>)</span><span>;</span></span> <span class="giallo-l"><span> reply_receiver</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">recv</span><span>(</span><span>)</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">unwrap_or</span><span>(</span><span style="color: light-dark(#005CC5, #79B8FF);">0</span><span style="color: light-dark(#005CC5, #79B8FF);">.</span><span style="color: light-dark(#005CC5, #79B8FF);">0</span><span>)</span></span> <span class="giallo-l"><span> }</span></span> <span class="giallo-l"></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> fn</span><span style="color: light-dark(#6F42C1, #B392F0);"> multiply</span><span>(</span><span style="color: light-dark(#D73A49, #F97583);">&amp;</span><span style="color: light-dark(#005CC5, #79B8FF);">self</span><span>,</span><span> a</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> f64</span><span>,</span><span> b</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> f64</span><span>)</span><span style="color: light-dark(#D73A49, #F97583);"> -&gt;</span><span style="color: light-dark(#6F42C1, #B392F0);"> f64</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span> (</span><span>reply_sender</span><span>,</span><span> reply_receiver</span><span>)</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span style="color: light-dark(#6F42C1, #B392F0);"> mpsc</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">channel</span><span>(</span><span>)</span><span>;</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span> _</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span style="color: light-dark(#005CC5, #79B8FF);"> self</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span>sender</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">send</span><span>(</span><span style="color: light-dark(#6F42C1, #B392F0);">CalculatorMessage</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">Multiply</span><span> {</span><span> a</span><span>,</span><span> b</span><span>,</span><span> reply</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span> reply_sender</span><span> }</span><span>)</span><span>;</span></span> <span class="giallo-l"><span> reply_receiver</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">recv</span><span>(</span><span>)</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">unwrap_or</span><span>(</span><span style="color: light-dark(#005CC5, #79B8FF);">0</span><span style="color: light-dark(#005CC5, #79B8FF);">.</span><span style="color: light-dark(#005CC5, #79B8FF);">0</span><span>)</span></span> <span class="giallo-l"><span> }</span></span> <span class="giallo-l"></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> fn</span><span style="color: light-dark(#6F42C1, #B392F0);"> divide</span><span>(</span><span style="color: light-dark(#D73A49, #F97583);">&amp;</span><span style="color: light-dark(#005CC5, #79B8FF);">self</span><span>,</span><span> a</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> f64</span><span>,</span><span> b</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span style="color: light-dark(#6F42C1, #B392F0);"> f64</span><span>)</span><span style="color: light-dark(#D73A49, #F97583);"> -&gt;</span><span style="color: light-dark(#6F42C1, #B392F0);"> Result</span><span>&lt;</span><span style="color: light-dark(#6F42C1, #B392F0);">f64</span><span>,</span><span style="color: light-dark(#6F42C1, #B392F0);"> String</span><span>&gt;</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span> (</span><span>reply_sender</span><span>,</span><span> reply_receiver</span><span>)</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span style="color: light-dark(#6F42C1, #B392F0);"> mpsc</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">channel</span><span>(</span><span>)</span><span>;</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span> _</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span style="color: light-dark(#005CC5, #79B8FF);"> self</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span>sender</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">send</span><span>(</span><span style="color: light-dark(#6F42C1, #B392F0);">CalculatorMessage</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">Divide</span><span> {</span><span> a</span><span>,</span><span> b</span><span>,</span><span> reply</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span> reply_sender</span><span> }</span><span>)</span><span>;</span></span> <span class="giallo-l"><span> reply_receiver</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">recv</span><span>(</span><span>)</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">unwrap_or</span><span>(</span><span style="color: light-dark(#6F42C1, #B392F0);">Err</span><span>(</span><span style="color: light-dark(#032F62, #9ECBFF);">&quot;</span><span style="color: light-dark(#032F62, #9ECBFF);">Communication error</span><span style="color: light-dark(#032F62, #9ECBFF);">&quot;</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">to_string</span><span>(</span><span>)</span><span>)</span><span>)</span></span> <span class="giallo-l"><span> }</span></span> <span class="giallo-l"></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> fn</span><span style="color: light-dark(#6F42C1, #B392F0);"> get_history</span><span>(</span><span style="color: light-dark(#D73A49, #F97583);">&amp;</span><span style="color: light-dark(#005CC5, #79B8FF);">self</span><span>)</span><span style="color: light-dark(#D73A49, #F97583);"> -&gt;</span><span style="color: light-dark(#6F42C1, #B392F0);"> Vec</span><span>&lt;</span><span style="color: light-dark(#6F42C1, #B392F0);">String</span><span>&gt;</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span> (</span><span>reply_sender</span><span>,</span><span> reply_receiver</span><span>)</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span style="color: light-dark(#6F42C1, #B392F0);"> mpsc</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">channel</span><span>(</span><span>)</span><span>;</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span> _</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span style="color: light-dark(#005CC5, #79B8FF);"> self</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span>sender</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">send</span><span>(</span><span style="color: light-dark(#6F42C1, #B392F0);">CalculatorMessage</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">GetHistory</span><span> {</span><span> reply</span><span style="color: light-dark(#D73A49, #F97583);">:</span><span> reply_sender</span><span> }</span><span>)</span><span>;</span></span> <span class="giallo-l"><span> reply_receiver</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">recv</span><span>(</span><span>)</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">unwrap_or_default</span><span>(</span><span>)</span></span> <span class="giallo-l"><span> }</span></span> <span class="giallo-l"></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> fn</span><span style="color: light-dark(#6F42C1, #B392F0);"> clear</span><span>(</span><span style="color: light-dark(#D73A49, #F97583);">&amp;</span><span style="color: light-dark(#005CC5, #79B8FF);">self</span><span>)</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span> _</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span style="color: light-dark(#005CC5, #79B8FF);"> self</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span>sender</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">send</span><span>(</span><span style="color: light-dark(#6F42C1, #B392F0);">CalculatorMessage</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">Clear</span><span>)</span><span>;</span></span> <span class="giallo-l"><span> }</span></span> <span class="giallo-l"></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> fn</span><span style="color: light-dark(#6F42C1, #B392F0);"> stop</span><span>(</span><span style="color: light-dark(#D73A49, #F97583);">&amp;</span><span style="color: light-dark(#005CC5, #79B8FF);">self</span><span>)</span><span> {</span></span> <span class="giallo-l"><span style="color: light-dark(#D73A49, #F97583);"> let</span><span> _</span><span style="color: light-dark(#D73A49, #F97583);"> =</span><span style="color: light-dark(#005CC5, #79B8FF);"> self</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span>sender</span><span style="color: light-dark(#D73A49, #F97583);">.</span><span style="color: light-dark(#6F42C1, #B392F0);">send</span><span>(</span><span style="color: light-dark(#6F42C1, #B392F0);">CalculatorMessage</span><span style="color: light-dark(#D73A49, #F97583);">::</span><span style="color: light-dark(#6F42C1, #B392F0);">Stop</span><span>)</span><span>;</span></span> <span class="giallo-l"><span> }</span></span> <span class="giallo-l"><span>}</span></span></code></pre> <p>분산 시스템이나 실시간 시스템, 높은 동시성이 필요한 시스템에서 좋게 써먹을 수 있다. 성능적으로도 그렇고 디자인적으로도 우수하다.</p> <h2 id="camjo">참조<a class="anchor" aria-hidden="true" href="#camjo" hidden="">#</a> </h2> <ul> <li><a rel="external" href="https://en.wikipedia.org/wiki/Actor_model">Actor Model</a></li> </ul>