| refer: [Bridging Async and Sync Rust Code - A lesson learned while working with Tokio |
Greptime](https://greptime.com/blogs/2023-03-09-bridging-async-and-sync-rust) |
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| impl Sequencer for PlainSequencer {
fn generate(&self) -> Vec<i32> {
let bound = self.bound;
futures::executor::block_on(async move {
RUNTIME.spawn(async move {
let mut res = vec![];
for i in 0..bound {
res.push(i);
tokio::time::sleep(Duration::from_millis(100)).await;
}
res
}).await.unwrap()
})
}
}
|
Best practice
Based on the above analysis and Rust’s generator-based cooperative asynchronous characteristics, we can summarize some tips when bridging asynchronous and synchronous code in Rust:
- Combining asynchronous code with synchronous code that can cause blocking is never a wise choice.
- When calling asynchronous code from a synchronous context, use
futures::executor::block_on and spawn the async code to a dedicated runtime, because the former will block the current thread.
- On the other hand, if you have to call blocking synchronous code from an asynchronous context, it is recommended to use
tokio::task::spawn_blocking to execute the code on a dedicated executor that handles blocking operations.
