Aria engine - changing block size
I found solution:


  
  change engine from aria to myisam
  stop mysql, add aria_block_size = 1024 to my.cnf
  delete aria_log_control file in mysql directory
  start mysql
  convert myisam tables back to aria
  


This process is safe for data, can be done without outage (only one fast mysql restart) and much faster then re-create tables and import data.