diff --git a/src/logic/future_moves.rs b/src/logic/future_moves.rs
index 0ba82f4..3fec03a 100644
--- a/src/logic/future_moves.rs
+++ b/src/logic/future_moves.rs
@@ -160,27 +160,31 @@ impl FutureMoves {
                 )
             };
 
-            self.leaf_moves()
+            let allowed_size = self.config.max_arena_size - self.arena.len();
+            let got = self
+                .leaf_moves()
                 .into_iter()
                 .filter(|&i| self.depth_of(i) == self.current_depth)
                 .collect::<Vec<usize>>()
                 .into_par_iter()
                 .progress_with_style(ProgressStyle::with_template(pstyle_inner).unwrap())
                 .map(|parent_idx| (parent_idx, self.generate_children_raw(parent_idx)))
-                .collect::<Vec<(usize, Vec<Move>)>>()
-                .into_iter()
-                .for_each(|(parent_idx, moves)| {
-                    let start_idx = self.arena.len();
-                    self.arena.extend(moves);
+                .take_any(allowed_size)
+                .collect::<Vec<(usize, Vec<Move>)>>();
+            let got_len = got.len();
 
-                    let new_indices = start_idx..self.arena.len();
-                    self.arena[parent_idx].children.extend(new_indices);
-                });
+            got.into_iter().for_each(|(parent_idx, moves)| {
+                let start_idx = self.arena.len();
+                self.arena.extend(moves);
+
+                let new_indices = start_idx..self.arena.len();
+                self.arena[parent_idx].children.extend(new_indices);
+            });
 
             self.prune_bad_children();
             self.current_depth += 1;
-
-            if self.arena.len() >= self.config.max_arena_size {
+            if got_len == allowed_size {
+                // got.len() has hit the upper limit of size permitted
                 break;
             }
         }
diff --git a/src/main.rs b/src/main.rs
index 631bf0a..f975fcd 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -32,7 +32,7 @@ fn main() {
         min_arena_depth: 14,
         top_k_children: 2,
         up_to_minus: 10,
-        max_arena_size: 400_000_000,
+        max_arena_size: 200_000_000,
         do_prune: true,
         print: true,
         children_eval_method: Default::default(),