SQL Virtual Database, DBCC CHECKDB command has been running for 18 hours

We desired to have a Virtual database to run the DBCC CHECKDB on the virtual database because the load it put on the production database slows down our users considerably.  A 20 Gb backup test worked fine.  A test on a 155 Gb backup gave an error on a latch.  I wanted to see if this is an isolated error, so I was testing on a 70 Gb backup and the test is over 18 hours old.  If the command can run in so many hours in production, it will meet my needs if it runs three times slower in the Virtual database environment.  Right now, I am nowhere close to that on this latest test.  Any suggestions are welcome.  Thanks.