berserk vs happy as a pig in shit

berserk

adj
  • Wildly joyous; ecstatic. 

  • Furiously, injuriously, or maniacally violent or out of control. 

  • Bizarre; weird. 

noun
  • Synonym of berserker (“a Norse warrior who fought in a frenzy”) 

happy as a pig in shit

adj
  • Extremely happy; obviously satisfied and carefree. 

How often have the words berserk and happy as a pig in shit occurred in a corpus of books? (source: Google Ngram Viewer )