increase the initial ibdata1 size, as explained in MySQL-5.6 revid:kevin.lewis@oracle.com-20120802192452-kmikiz990xzje18b

"
  A maximum size of 10 Mb works in 5.1 because the initial
  required size of ibdata1 was less than 10M.  But in 5.5, a
  change was made to allocate all 128 rollback segments at
  bootstrap.  Since then, the initial size has been 10M + the
  default autoextend size of 8M. 

  In 5.6, worklog 6216 changes the autoextend size from 8M to
  64M.  This changes the initial size of ibdata1 from 18M in
  5.5 and earlier releases of 5.6 to 74M in the current
  mysql-5.6 and mysql-trunk.  So this change is especially
  needed in 5.6.
"

12M is enough to avoid autoextending during bootstrap