Commit 884b1423a4

@@ -69,9 +69,22 @@ pub fn MemoryPoolExtra(comptime Item: type, comptime pool_options: Options) type
         pub fn initPreheated(allocator: std.mem.Allocator, initial_size: usize) MemoryPoolError!Pool {
             var pool = init(allocator);
             errdefer pool.deinit();
+            try pool.preheat(initial_size);
+            return pool;
+        }
+
+        /// Destroys the memory pool and frees all allocated memory.
+        pub fn deinit(pool: *Pool) void {
+            pool.arena.deinit();
+            pool.* = undefined;
+        }
 
+        /// Preheats the memory pool by pre-allocating `size` items.
+        /// This allows up to `size` active allocations before an
+        /// `OutOfMemory` error might happen when calling `create()`.
+        pub fn preheat(pool: *Pool, size: usize) MemoryPoolError!void {
             var i: usize = 0;
-            while (i < initial_size) : (i += 1) {
+            while (i < size) : (i += 1) {
                 const raw_mem = try pool.allocNew();
                 const free_node = @as(NodePtr, @ptrCast(raw_mem));
                 free_node.* = Node{
@@ -79,14 +92,6 @@ pub fn MemoryPoolExtra(comptime Item: type, comptime pool_options: Options) type
                 };
                 pool.free_list = free_node;
             }
-
-            return pool;
-        }
-
-        /// Destroys the memory pool and frees all allocated memory.
-        pub fn deinit(pool: *Pool) void {
-            pool.arena.deinit();
-            pool.* = undefined;
         }
 
         pub const ResetMode = std.heap.ArenaAllocator.ResetMode;