DATA STORAGE, PERSISTENT STORAGE,

 

Dynamic Data: Are data that changes. for example; If you have a gmail account, you can change the profile around your account or you can change your recovery email and other information within that data. The reason why you're able to accomplish that is because its dynamic.

Static Data: Are data that cannot be changed. For example, A file within your bucket cannot be changed. 

Block Storage: Disk or drives are used to store data. Another name for it is called volume. Whenever you create a virtual machine in GCP it comes with a disk in which the data is stored inform of blocks. 

Persistent Disk: This is a durable network storage device that your instance can access. It can serve as a data store and application and to maximize latency for data storage. When it comes with the existence, its durable, and cannot get corrupt. You can only assign one persistent disk to a virtual machine.You can create a snap shot. By default Google cloud ensure that the data stored inside the block storage  is encrypted. for example, you provisioned 50GB after few months your workload increased you can resize the volume. Persistent disk volumes can be up to 64 TB in size. The maximum attached capacity for persistent disk is 257 TB per VM instance. 

a. Regional Persistent Disk: This span across availability zones. As long as that disk is available in that region your data will available for disaster recovery. 

Two types of persistent disk:

a. Hard disk disk blocked Persistent disk: This is streaming storage workload and throughout must be define by speed in which data can be transferred, translated in MB per seconds. The throughput provides the best latency to communicate from one region to another region in terms of data transfer.

b. Solid State drive: Google cloud provides you the ability to perform IOPS which means how quick a transaction can be processed to either read data or write data. 

IOPS  means Input and output operations per second. 

Standard Persistent disk : This is suitable for large data processing workload and its backed by hard disk drive. 

Extreme persistent disk: You can customize the IOPS and the cost will depend on what you provisioned. 

Balanced Persistent disk: This is backed by solid state drive and its cost effective. You can attach a balanced persistent disk to a maximum of 10 VM instance in a read only access.

Local disk: Its a physical disk that rely on host. Its not possible to attach local disk to a private VM in your private on-premises. However, you can migrate the data, use snapshot and its faster. But if you stop the VM, you will lose all the data because its ephemeral.

Auto-delete zonal persistent disk: You can automatically delete read/write persistent disks if its associated with VM instance.

Referencing : Google documentation.