What nobody seems to mention is the impact innodb_undo_log_truncate setting can have.
After reading Percona's blog post about the topic, I've enabled in my MariaDB 10.6 the truncation of UNDO LOG entries which filled 95% of ibdata1, and, after a complete drop and restore, from that moment on my ibdata1 never grew anymore.
With the default innodb_undo_log_truncate = 0 my ibdata1 easily reached 10% of databases space occupation, aka tens of Gigabytes.
With innodb_undo_log_truncate = 1, ibdata1 it's firm at 76 Mb.
