Hello Germano, our development have built a lab of 5 ESX hosts and 30 VM, and did a stress testing on it - and the transaction logs size was only 30MB. So, they are not sure why in your case it increases up to 500MB.
To address transaction log growth, you could try to set AutoShrink parameter to TRUE in Monitor SQL database settings. You could also run shring manually with the following command, but Microft does not really recommend this because it affects database performance, and our product is using the database actively.
DBCC SHRINKFILE(Monitor_log, TRUNCATEONLY)