This is fairly common to massive data load into Dynamics 365. Here you can find useful link to bulk load. As you know there are some constraints while accessing Dynamics 365 over SDK (Microsoft.Xrm.Sdk.Client.OrganizationServiceProxy):
- 1000 requests in Microsoft.Xrm.Sdk.Messages.ExecuteMultipleRequest
- 2 concurrent Microsoft.Xrm.Sdk.Messages.ExecuteMultipleRequest
Firstly, you need to instantiate Microsoft.Xrm.Sdk.Client.OrganizationServiceProxy class and open the WCF channel to your CRM Organization. Then within a new Task create a new instance of OrganizationServiceProxy using recent instances of IServiceManagement and SecurityTokenResponse variables.
Each OrganizationServiceProxy instance created within a Task can keep impersonated user.
You would also need to feed variable actionRequest of Microsoft.Xrm.Sdk.Messages.ExecuteMultipleRequest which can be any of OrganizationRequest type.
