Storage Systems

Question 1

3 types of Storage Systems

Answer 1

Cache, Persistent, Object

Question 2

Example of cache in GC

Answer 2

Memory Store - managed Redis service

Question 3

1 benefit of cache

Answer 3

low latency - sub-millisecond access

Question 4

3 problems of cache

Answer 4

1. volatile - lost when machine shuts down
2. more expensive than SSD or HDD
3. can get out of sync with the system of truth (persistent storage)

Question 5

Cache - quick definition

Answer 5

in memory data store

Question 6

Persistent Storage - quick definition

Answer 6

durable block storage

Question 7

Where can you use persistent storage?

Answer 7

Can be attached to VMs in Compute Engine and Kubernetes Engine.

Question 8

Where is persistent storage located?

Answer 8

On the network. They are not attached to the physical servers hosting your VM. They exist independently of VMs.

Question 9

Can a VM have locally attached persistent storage?

Answer 9

Yes. VM can have local SSD, but it is volatile.

Question 10

Types of persistent storage

Answer 10

SSD and HDD

Question 11

Differences between SSD and HDD

Answer 11

HDD have higher latency, but lower cost.

Network attached SSD are 40/20 times faster (R/W) than HDD. Locally attached SSD are 200/150 times faster.

Question 12

Max size of SSD/HDD

Answer 12

64TB

Question 13

4 facts of persistent storage

Answer 13

1. can create file systems on them
2. data is automatically encrypted
3. size can be increased while mounted to VM
4. can be mounted in read-only mode on multiple VMs at once

Question 14

Is persistent storage zonal or regional?

Answer 14

Both. Regional replicates data across different zones, but is more expensive than purely zonal storage.

Question 15

What is Object Storage good for?

Answer 15

large volumes of data that is shared widely

Question 16

3 storage data models

Answer 16

1. object
2. relational
3. NoSQL

Question 17

GC app example of object model storage

Answer 17

Cloud Store

Question 18

How are object model objects stored?

Answer 18

Atomically. Cannot read parts of an object. Must copy to server, make changes and then copy object back to object storage system. Used when you don’t need fine-grained access to data within the object while it is in the object store

Question 19

3 GC app examples of Relational model storage

Answer 19

1. Cloud SQL
2. Cloud Spanner
3. Big Query

Question 20

3 facts of Relational model storage

Answer 20

1. supports frequent queries and updates to data
2. allows for consistent view of data
3. supports database transactions (Cloud SQL and Cloud Spanner)

Question 21

3 GC app examples of NoSQL model storage

Answer 21

1. Cloud Datastore
2. Cloud Firestore
3. Bigtable

Question 22

Benefits/Limitations of 3 types of Storage systems.

Answer 22

1. cache is fastest but most expensive and volatile.
2. persistent is used for things that need block storage. SSD are faster but more expensive.
3. object storage used for large volumes of data for long periods of time.

Question 23

5 things to consider when planning object storage

Answer 23

1. frequency of read/write
2. consistency
3. transaction support
4. cost
5. latency

Question 24

Planning storage - frequency of read/write

Best for structured data that is frequently accessed

Answer 24

Cloud SQL

Question 25

Planning storage - frequency of read/write | Best for global database that supports relational read/writes

Answer 25

Cloud Spanner

Question 26

Planning storage - frequency of read/write | Best for writing data at high rates and in large volumes

Answer 26

Bigtable

Question 27

Planning storage - frequency of read/write | Best for writing files and downloading them in their entirety

Answer 27

Cloud Store

Question 28

``` Planning Storage - Consistency Strongest consistency (2) ```

Answer 28

Cloud SQL | Cloud Spanner

Question 29

Planning Storage - Consistency | Good for unstructured data

Answer 29

Datastore

Question 30

Planning Storage - Transaction Support | 3 apps that support transactions

Answer 30

Cloud SQL Cloud Spanner Datastore

Question 31

Planning Storage - Latency | Fastest

Answer 31

Bigtable

Question 32

Planning Storage - Latency | Globally consistent and scalable

Answer 32

Cloud Spanner