At 1:15 PM UTC, the Microsoft team completed mitigation for a subset of CRM Online customers (<10% of those in the region) who may not have been able to access CRM Online earlier today.
The root cause was at least partly a known SQL Server bug for which we are in the process of deploying a SQL Hotfix to all servers globally. Without the hotfix, SQL Server consumes all available memory over time until it becomes unresponsive.
Deployment of the hotfix is underway in North America. Next it will be deployed to servers in Europe and Asia.