Create account paths once

(cherry picked from commit fe0ba4a429)

runtime/src/serde_snapshot.rs

@@ -288,6 +288,12 @@ where
         map
     };
 
+    // Ensure all account paths exist
+    for path in &accounts_db.paths {
+        std::fs::create_dir_all(path)
+            .unwrap_or_else(|err| panic!("Failed to create directory {}: {}", path.display(), err));
+    }
+
     let mut last_log_update = Instant::now();
     let mut remaining_slots_to_process = storage.len();
 
@@ -307,8 +313,6 @@ where
                 let path_index = thread_rng().gen_range(0, accounts_db.paths.len());
                 let local_dir = &accounts_db.paths[path_index];
 
-                std::fs::create_dir_all(local_dir).expect("Create directory failed");
-
                 // Move the corresponding AppendVec from the snapshot into the directory pointed
                 // at by `local_dir`
                 let append_vec_relative_path = AppendVec::new_relative_path(slot, storage_entry.id);