As organizations increasingly move into the cloud, performance is a growing concern. Cloud applications need to be monitored and managed to ensure that they are available and responsive:
Your application is dependent upon many services. To run these applications, you need to manage the alerts that come in from every service. When is a service going to be down? What are the notifications? Are there response time issues? Then you have to track and monitor the notifications and response time, error rates, etc., for those services you can manage.
Check out the full post, Q&A: What You Need to Know When Adopting Enterprise Cloud Services, from SearchSOA.