Values.EbsBlockDeviceConfigSourceConfiguration of requested EBS block device associated with the instance group with count of volumes that are associated to every instance.
type nonrec t = {volumeSpecification : VolumeSpecification.t;EBS volume specifications such as volume type, IOPS, size (GiB) and throughput (MiB/s) that are requested for the EBS volume attached to an Amazon EC2 instance in the cluster.
*)volumesPerInstance : Integer.t option;Number of EBS volumes with a specific volume configuration that are associated with every instance in the instance group
*)}