I was researching slow performence issue when InsertImage.aspx is displayed and I have discovered that GetDirectory size is invoked twice.

 

This method is invoked when displaying the amount of space used:

And it's invoked a second time to calculate the percentage of space used:
protected int GetUsedPercent() {
   int w = Convert.ToInt32(100*fs.GetDirectorySize(fs.VirtualRoot)/(secset.MaxImageFolderSize * 1024));
   if(w<1)
      w=1;
   if(w>100)
      w=100;
   return w;
}

This is obviously ineficient and causes the file repository to be scanned twice. I know some users have complained that the image galery is slow to open when there's a large number of files in the repository, I think InsertImage.aspx can be improved to make sure this method is invoked only once and therfore improve performance.