The best replacement for innodb is myisam.

The best alternatives to innodb are rated as following:
★★★★★  myisam
★★★  isam
★★★  myisam performance
★★  xtradb
★★  ndb
★★  bdb
★★  myisam speed
★  myisam which is better
★  myisam faster
★  myisam mysql database
★  aria
★  myisam check
★  myisam prestashop
★  myisam wordpress
★  myisam insert speed
★  myisam select performance
★  tokudb
  myisam differences
  myisam full text search
  myisam benchmark
  myisam mysql

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Speaking about innodb, one probably shouldn't forget about mysql.

Other search terms related to innodb and their ratings are:
★★★★★ mysql
★★★ myisam
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