When VMware and Amazon Web Services, the internet retailer’s cloud unit, formed a partnership in 2016, some in the tech industry were skeptical that the agreement between the two rivals would amount to much.  

Now it looks like the result of that pact—a joint service that lets VMware’s corporate customers move computing jobs between their own data centers and AWS—is paying off after a sluggish start in late 2017. While customer usage of the service generated only around $25 million in AWS fees in 2018, that figure was roughly $15 million for the first month of this year alone, according to two people with direct knowledge of the business. If it continues at this pace, VMware Cloud on AWS, as the joint service is known, could result in around $100 million in AWS fees this year, one of the people said.