Complex sentence: Thoroughly obsolete by that point, she saw little action and returned to barracks duties after the war, remaining in the fleet's inventory through the 1920s, being decommissioned in 1929 and broken up thereafter.
Split into simpler sentences: Thoroughly obsolete by that point, she saw little action and returned to barracks duties after the war. The ship remained in the fleet's inventory through the 1920s, being decommissioned in 1929 and broken up thereafter.