add multithreading

Cargo.lock

@@ -183,6 +183,7 @@ dependencies = [
  "enum-iterator",
  "env_logger",
  "float-ord",
+ "futures-util",
  "log",
  "rand",
  "serde",
@@ -516,6 +517,17 @@ version = "0.3.31"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "05f29059c0c2090612e8d742178b0580d2dc940c837851ad723096f87af6663e"
 
+[[package]]
+name = "futures-macro"
+version = "0.3.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "162ee34ebcb7c64a8abebc059ce0fee27c2262618d7b60ed8faf72fef13c3650"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "futures-sink"
 version = "0.3.31"
@@ -535,6 +547,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9fa08315bb612088cc391249efdc3bc77536f16c91f6cf495e6fbe85b20a4a81"
 dependencies = [
  "futures-core",
+ "futures-macro",
  "futures-sink",
  "futures-task",
  "pin-project-lite",