spawn blocking task for simulations

Cargo.lock

@@ -188,6 +188,12 @@ dependencies = [
  "tokio",
 ]
 
+[[package]]
+name = "bitflags"
+version = "2.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8f68f53c83ab957f72c32642f3868eec03eb974d1fb82e453128456482613d36"
+
 [[package]]
 name = "bitvec"
 version = "1.0.1"
@@ -739,6 +745,16 @@ version = "0.2.169"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b5aba8db14291edd000dfcc4d620c7ebfb122c613afb886ca8803fa4e128a20a"
 
+[[package]]
+name = "lock_api"
+version = "0.4.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "07af8b9cdd281b7915f413fa73f29ebd5d55d0d3f0155584dade1ff18cea1b17"
+dependencies = [
+ "autocfg",
+ "scopeguard",
+]
+
 [[package]]
 name = "log"
 version = "0.4.25"
@@ -830,6 +846,29 @@ version = "11.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b410bbe7e14ab526a0e86877eb47c6996a2bd7746f027ba551028c925390e4e9"
 
+[[package]]
+name = "parking_lot"
+version = "0.12.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f1bf18183cf54e8d6059647fc3063646a1801cf30896933ec2311622cc4b9a27"
+dependencies = [
+ "lock_api",
+ "parking_lot_core",
+]
+
+[[package]]
+name = "parking_lot_core"
+version = "0.9.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1e401f977ab385c9e4e3ab30627d6f26d00e2c73eef317493c4ec6d468726cf8"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "redox_syscall",
+ "smallvec",
+ "windows-targets",
+]
+
 [[package]]
 name = "percent-encoding"
 version = "2.3.1"
@@ -959,6 +998,15 @@ dependencies = [
  "crossbeam-utils",
 ]
 
+[[package]]
+name = "redox_syscall"
+version = "0.5.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "03a862b389f93e68874fbf580b9de08dd02facb9a788ebadaf4a3fd33cf58834"
+dependencies = [
+ "bitflags",
+]
+
 [[package]]
 name = "regex"
 version = "1.11.1"
@@ -1015,6 +1063,12 @@ dependencies = [
  "winapi-util",
 ]
 
+[[package]]
+name = "scopeguard"
+version = "1.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"
+
 [[package]]
 name = "serde"
 version = "1.0.217"
@@ -1080,6 +1134,15 @@ dependencies = [
  "digest",
 ]
 
+[[package]]
+name = "signal-hook-registry"
+version = "1.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a9e9e0b4211b72e7b8b6e85c807d36c212bdb33ea8587f7569562a84df5465b1"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "slab"
 version = "0.4.9"
@@ -1174,7 +1237,9 @@ dependencies = [
  "bytes",
  "libc",
  "mio",
+ "parking_lot",
  "pin-project-lite",
+ "signal-hook-registry",
  "socket2",
  "tokio-macros",
  "windows-sys 0.52.0",

battlesnake/Cargo.toml

@@ -17,7 +17,7 @@ nursery = "warn"
 
 [dependencies]
 # server
-tokio = { version = "1.43", features = ["net", "macros", "rt-multi-thread"] }
+tokio = { version = "1.43", features = ["full"] }
 axum = { version = "0.8", features = ["http2", "multipart", "ws"] }
 serde = { version = "1.0", features = ["derive", "rc"] }
 

battlesnake/src/main.rs

@@ -82,46 +82,60 @@ async fn get_move(request: Json<Request>) -> response::Json<Response> {
     }
     info!("valid actions: {:?}", actions);
 
-    let mut action_data = [(0, 0); 4];
+    tokio::task::spawn_blocking(move || {
-    let mut total_simulations = 0;
+        let base_turns = board.turn();
-    let base_turns = board.turn();
+        let end_condition: &dyn Fn(&Board) -> Option<u32> = match &*request.game.ruleset.name {
-    while start.elapsed() < Duration::from_millis(250) {
+            "solo" => &|board: &Board| {
-        let mut board = board.clone();
+                if board.num_snakes() == 0
-        let action = *actions.choose(&mut thread_rng()).unwrap_or(&Direction::Up);
+                    || board.turn() > base_turns + u32::from(request.you.length) * 3
-        board.next_turn(&[(id, action)]);
+                {
-        let turns = board.simulate_random(|board| {
+                    Some(board.turn())
-            if board.num_snakes() == 0
+                } else {
-                || board.turn() > base_turns + u32::from(request.you.length) * 3
+                    None
-            {
+                }
-                Some(board.turn())
+            },
-            } else {
+            _ => &|board: &Board| {
-                None
+                if !board.alive(id) || board.turn() > base_turns + u32::from(request.you.length) * 3
-            }
+                {
+                    Some(board.turn())
+                } else {
+                    None
+                }
+            },
+        };
+
+        let mut action_data = [(0, 0); 4];
+        let mut total_simulations = 0;
+        while start.elapsed() < Duration::from_millis(250) {
+            let mut board = board.clone();
+            let action = *actions.choose(&mut thread_rng()).unwrap_or(&Direction::Up);
+            board.next_turn(&[(id, action)]);
+            let turns = board.simulate_random(end_condition);
+            let action_data = &mut action_data[usize::from(action)];
+            action_data.0 += turns - base_turns;
+            action_data.1 += 1;
+            total_simulations += 1;
+        }
+        debug!("action data: {action_data:?}");
+
+        let action = actions.into_iter().max_by_key(|action| {
+            let action_data = action_data[usize::from(*action)];
+            (action_data.0 / action_data.1, action_data.0 % action_data.1)
         });
-        let action_data = &mut action_data[usize::from(action)];
-        action_data.0 += turns - base_turns;
-        action_data.1 += 1;
-        total_simulations += 1;
-    }
-    debug!("action data: {action_data:?}");
 
-    let action = actions.into_iter().max_by_key(|action| {
+        if let Some(action) = action {
-        let action_data = action_data[usize::from(*action)];
+            let action_data = action_data[usize::from(action)];
-        (action_data.0 / action_data.1, action_data.0 % action_data.1)
+            let avg_turns = action_data.0 / action_data.1;
-    });
+            info!("found action {action:?} after {total_simulations} simulations with an average of {avg_turns} turns.");
-
+        } else {
-    if let Some(action) = action {
+            warn!("unable to find a valid action");
-        let action_data = action_data[usize::from(action)];
+        }
-        let avg_turns = action_data.0 / action_data.1;
+        info!("chose {action:?}");
-        info!("found action {action:?} after {total_simulations} simulations with an average of {avg_turns} turns.");
+        response::Json(Response {
-    } else {
+            direction: action.unwrap_or(Direction::Up),
-        warn!("unable to find a valid action");
+            shout: None,
-    }
+        })
-    info!("chose {action:?}");
+    }).await.unwrap()
-    response::Json(Response {
-        direction: action.unwrap_or(Direction::Up),
-        shout: None,
-    })
 }
 
 async fn end(request: Json<Request>) {