advanced patterns when using async/await with Tokio and shared state in Rust
I've been struggling with this for a few days now and could really use some help. I've spent hours debugging this and I've searched everywhere and can't find a clear answer... I'm working on a Rust project using Tokio for asynchronous programming. I have a scenario where multiple async tasks need to access and modify a shared state, which is wrapped in an `Arc<Mutex<>>`. However, I'm running into unexpected behavior where the state seems to be getting corrupted. Here’s a minimal example: ```rust use std::sync::{Arc, Mutex}; use tokio::task; struct SharedState { value: i32, } #[tokio::main] async fn main() { let state = Arc::new(Mutex::new(SharedState { value: 0 })); let mut handles = vec![]; for _ in 0..10 { let state_clone = Arc::clone(&state); let handle = task::spawn(async move { let mut data = state_clone.lock().unwrap(); data.value += 1; }); handles.push(handle); } for handle in handles { let _ = handle.await; } println!("Final value: {}", state.lock().unwrap().value); } ``` When I run this code, I expect the final value to be 10, but I sometimes get lower values, like 8 or 9, which indicates that some increments are lost. My Tokio version is 1.15.0, and I wonder if this is due to not properly handling the Mutex or if there's something else at play. I've ensured that each task is awaited, so I'm not sure where the scenario lies. Am I missing something fundamental about async task execution in Rust? I'd really appreciate any guidance on this. This is part of a larger service I'm building. I'd be grateful for any help. For context: I'm using Rust on Ubuntu 22.04. Hoping someone can shed some light on this.