How run async method multiple times in separate threads?

Question

I am newbie in using of await/async and windows phone 8.1 programming. I need to run async method simulateously in more than one thread. May be four, because my phone has four cores. But i cannot figure it out :-(

This is example of my async method.

public async Task GetFilesAsyncExample(StorageFolder root)
{
        IReadOnlyList<StorageFolder> folders = await root.GetFoldersAsync(); 
        //DO SOME WORK WITH FOLDERS//
}

Four threads can be ensured by using of a semaphore object, but how i can run it in simulatously running threads?

EDIT: This is my code which explores folder structure and log metadata about files into database. I want to speed up execution of this code by calling method "async LogFilesFromFolderToDB(StorageFolder folder)" simulateously in separate thread for each folder.

 Stack<StorageFolder> foldersStack = new Stack<StorageFolder>();
            foldersStack.Push(root);
            while (foldersStack.Count > 0)
            {
                StorageFolder currentFolder = foldersStack.Pop();
                await LogFilesFromFolderToDB(null, currentFolder);// Every call of this method can be done in  a separate thread.
                IReadOnlyList<StorageFolder> folders = await currentFolder.GetFoldersAsync();
                for (int i = 0; i < folders.Count; i++)
                    foldersStack.Push(folders[i]);
            }

Method: async LogFilesFromFolderToDB(StorageFolder folder) looks like:

   async Task LogFilesFromFolderToDB(StorageFolder folder)
    {
        IReadOnlyList<StorageFile> files = await folder.GetFilesAsync();
        //SOME ANOTHER CODE//
    }

Answer 1

Parallel.Foreach can help to resolve this issue.

Try the below code,

 public async Task GetFilesAsyncExample(StorageFolder root)
    {
        IReadOnlyList<StorageFolder> folders = await root.GetFoldersAsync();

        Parallel.ForEach(folders, (currentFolder) =>
        {
            Console.WriteLine("folder name:" + currentFolder.Name + " Files count" + currentFolder.GetFiles().Count());
        });
        //DO SOME WORK WITH FOLDERS//
    }