Complex sentence: While the single wasn't a commercial success, having not charted; it remains one of their best known numbers, being the second most performed song by the band, following "The (Billion Day) Funeral".
Split into simpler sentences: While the single wasn't a commercial success, having failed to chart, it remains one of their best known songs. It is the second most performed song by the band, after "The (Billion Day) Funeral".