A Survey on Cloud Storage Systems

Team : Xiaoming

Xiaogang

Adarsh

Abhijeet

Pranav

A Survey on Cloud Storage Systems

Motivations



No Taxonomy



Detailed Survey for users

Taxonomy

Category

Definition

Example

Instance Storage

Storage coming with virtual machine images

Amazon EC2 instance storage

Object storage

Storage of binary objects provided in the form of Web services.

An object can be any type of file.

Amazon Simple Storage Service (S3)

Block storage

Virtual block devices that can be attached to VM instances and

used like local disks.

Amazon Elastic Block Store (EBS)

Semi-structured data

storage

Database service for storing semi-structured data with high

availability, high scalability, and high performance.

Amazon Simple DB

Relational Database storage

Relational database servers on VM instances in clouds.

Amazon Relational Database service

Distributed file system

Distributed storage provided through file system interfaces

with high availability and high scalability.

Google File System

Online Drive/

Folder service

Storage space provided in the form of a virtual drive or folder

on Internet.

Commercial Cloud Providers

Vendor

Instance

storage

Object

storage

Block

storage

Semi-structured

data

storage

Relational

Database

storage

Distributed

File System

Online

Folder/Drive

Amazon

EC2

S3

EBS

SimpleDB

RDS

N/A

Microsoft

Azure VM

Azure Blob

Azure

drive

Azure table

SQL Azure

N/A

SkyDrive/Mesh

Google

N/A

Google

Storage for

Developers

N/A

BigTable

N/A

Google File

System

Commercial Cloud Providers

B649 - Project Proposal Presentation



Windows

Azure Blob

- Distributed storage for large items. Each item can be of maximum size 50 GB.

- One can view Azure Blob as a container. Each container consists of blobs and each blob is made of blocks. - All access to Azure Blob is through HTTP REST interface.



Windows SQL Azure

- SQL Azure provides web-facing database functionality as utility service. - TDS is the protocol which is used to connect to a Cloud-based database. - Queries are formulated in Transact-SQL language.

- Applications and tools already in use with existing other relational databases work seamlessly with SQL Azure.



Windows Azure Table

- Provides structured storage for maintaining service state.

- Structured storage is provided in the form of tables which contain a set entities and each entity is made up of a set of named properties. - Provides support for LINQ, ADO.NET data services and REST.

Commercial Cloud Providers



Amazon Elastic Block Store (EBS)

- Off-instance storage that persists independently from the life of an instance. - Storage volumes behave like raw, unformatted, block devices.

- Can store from 1 GB to 1 TB in storage volumes, can be mounted on EC2 instances.



Amazon S3

- Object storage that is designed to make web-scale computing easier for developers. - Users can store persistent data organized in buckets and objects.

- Uses standards-based REST and SOAP interfaces designed to work with any Internet- development toolkit. - Unlimited objects containing 1 byte to 5 GB of data each can be stored.



Amazon Relational Database Storage (RDS)

- Provides cost-effective and resizable storage capacity.

- Applications and tools in use with existing MySQL databases work seamlessly with Amazon RDS.



Amazon SimpleDB

- Non-relational database that offloads the work of database administration.

Commercial Cloud Providers

Commercial Cloud Providers - Use Cases



_{Creating a Web Application With Relational Data}

SQL Azure or Amazon RDS can be used



Creating parallel processing Application, Storage for data analysis, Backup and Recovery

(examples: financial modeling at a bank,

New drug development in a pharmaceutical company.)

Azure Blob or Amazon S3 can be used to store intermediate data.



Creating Scalable Web Application, gaming application, metadata indexing

(example : On line Tickiet system, news video site etc ,)

Azure table or Amazon Simple DB can be used



_{Applications that require a database, file system, or access to raw block level storage.}

Academic Cloud Systems

B649 - Project Proposal Presentation

System

Instance

storage

Object

storage

Block

storage

Semi-structured

data storage

Distributed file system

Eucalyptus

VM

S3

EBS

N/A

N/A

Nimbus

VM

Cumulus

N/A

N/A

N/A

OpenNebula

VM

N/A

N/A

N/A

N/A

OpenStack

VM

OpenStack

object storage

N/A

N/A

N/A

Hadoop

N/A

N/A

N/A

HBase

Hadoop distributed file

system (HDFS)

Academic Cloud Systems



Eucalyptus

Walrus

SOAP/REST based tools

Storage Controller

…

Storage Controller

…

Cluster A

Cluster B



S3 mainly used for VM image storage

Academic Cloud Systems

B649 - Project Proposal Presentation



Nimbus

- Cumulus service used for VM image storage

- Cumulus can be configured to use various storage backend



OpenNebula

-Two ways to manage VM images: shared NFS and

non-shared SSH

Academic Cloud Systems



OpenStack

- OpenStack object storage used for VM image management

- Uses disk blocks directly instead of file systems



Hadoop

- HDFS interface is not totally compatible with POSIX

standard, nor is the system optimized for file I/Os

Conclusions and Future work



Virtualized I/O performance of cloud storage services not

comparable to local disk yet



Academic cloud systems are not providing a rich set of

storage services so far



Performance tests for commercial storage services in future



More investigation on design and implementation details