Use single-threaded hashmap instead of dashmap

Address performance regressions

Cargo.lock

@@ -442,7 +442,6 @@ dependencies = [
  "criterion",
  "dagrs",
  "dagx-macros",
- "dashmap",
  "futures",
  "futures-executor",
  "parking_lot",
@@ -462,20 +461,6 @@ dependencies = [
  "syn 2.0.106",
 ]
 
-[[package]]
-name = "dashmap"
-version = "6.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5041cc499144891f3790297212f32a74fb938e5136a14943f338ef9e0ae276cf"
-dependencies = [
- "cfg-if",
- "crossbeam-utils",
- "hashbrown",
- "lock_api",
- "once_cell",
- "parking_lot_core",
-]
-
 [[package]]
 name = "either"
 version = "1.15.0"
@@ -656,12 +641,6 @@ dependencies = [
  "crunchy",
 ]
 
-[[package]]
-name = "hashbrown"
-version = "0.14.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e5274423e17b7c9fc20b6e7e208532f9b19825d82dfd615708b70edd83df41f1"
-
 [[package]]
 name = "hermit-abi"
 version = "0.5.2"

Cargo.toml

@@ -32,7 +32,6 @@ futures = "0.3"
 parking_lot = "0.12"
 dagx-macros = { version = "0.3.1", path = "./dagx-macros" }
 tracing = { version = "0.1", optional = true }
-dashmap = "6.1.0"
 
 [dev-dependencies]
 tokio = { version = "1", features = [

src/runner.rs

@@ -13,7 +13,6 @@ use std::sync::{
     Arc,
 };
 
-use dashmap::DashMap;
 use futures::stream::FuturesUnordered;
 use futures::{FutureExt, StreamExt, TryFutureExt};
 use parking_lot::Mutex;
@@ -314,7 +313,7 @@ impl DagRunner {
 
         let edges = self.edges.lock().clone();
 
-        let outputs: DashMap<NodeId, Arc<dyn Any + Send + Sync>> = DashMap::new();
+        let mut outputs: HashMap<NodeId, Arc<dyn Any + Send + Sync>> = HashMap::new();
         let mut first_error = None;
 
         for layer in layers {
@@ -414,7 +413,6 @@ impl DagRunner {
             } else {
                 // Slow path: Multiple tasks require spawning and coordination
                 // Spawn each task in this layer
-                let outputs = &outputs;
                 let mut futures: FuturesUnordered<_> = FuturesUnordered::new();
                 layer
                     .into_iter()
@@ -437,8 +435,7 @@ impl DagRunner {
                             // Spawn the task using the provided spawner
                             let inner_future = async move {
                                 let result = node.execute_with_deps(dependencies).await?;
-                                outputs.insert(node_id, result);
-                                Ok(())
+                                Ok((node_id, result))
                             };
 
                             Some(
@@ -477,8 +474,13 @@ impl DagRunner {
                     .for_each(|fut| futures.push(fut));
 
                 while let Some(out) = futures.next().await {
-                    if let Err(e) = out {
-                        first_error.get_or_insert(e);
+                    match out {
+                        Ok(output) => {
+                            outputs.insert(output.0, output.1);
+                        }
+                        Err(e) => {
+                            first_error.get_or_insert(e);
+                        }
                     }
                 }
             }