InnoDB disk file grows, never shrinks

[Michael S]

My InnoDB file is set to 60MB, and is not set to autoexpand.

When running stress tests against my server today, I got a message that the table was full
and the test stopped. Sure enough, the InnoDB file was about 62MB.

My question:
I assume that the InnoDB file is the transaction log. Is there a command that I should be
running to truncate the transaction log periodically so it doesn't fill up? On MS SQL
Server, I can run with TRUNCATE LOG ON CHECKPOINT if running in a test scenario.

TIA,
-ms