preserver vs upholder

preserver

noun
  • One who preserves. 

  • A person who prepares preserves of fruit or preserved meats. 

  • A person who refinishes furniture. 

  • A life preserver. 

upholder

noun
  • Someone who upholds something. 

How often have the words preserver and upholder occurred in a corpus of books? (source: Google Ngram Viewer )