13.0 The Cloud The Cloud The Cloud The Cloud The Cloud 7/16/2010. Distributed Data Management

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1 Distributed Data Management Wolf-Tilo Balke Christoph Lofi Institut für Informationssysteme Technische Universität Braunschweig Cloud beyond Storage 13.1 Computing as a Service SaaS PaaS IaaS Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 2 The term cloud computing is often seen as a successor of client-server architectures Often used as synonym for centralized on-demand pay-what-you-use provisioning of general computation resources e.g. compared to utility providers like electric power grids or water supply Computing as a commodity Cloud is used as a metaphor for the Internet Users or applications just use computation resources provided in the internet instead using local hardware or software Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 3 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 4 Computation resources can mean a lot of things: Dynamic access to raw metal Raw storage space or CPU time Fully operational server are provided by the cloud Low-level services and platforms e.g. runtime platforms like Jave JRE» User can run application directly on cloud platform» No own servers or platform software needed e.g. abstracted storage space like space within a database or a file system» This is what we did in the last weeks! Software services i.e. some functionalities required by user software is provided by the cloud» Used via web service remote procedure calls» e.g. delegate a the rendering of a map in a user applciarion to Google Maps Full software functionality e.g. rented web applications replacing traditional server or desktop applications» e.g. rent CRM software online from SalesForce, use Google apps instead of MS Office, etc. Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 5 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 6 1

2 Underlying base problem Successfully running IT departments and IT infrastructure can be very difficult and expensive for companies High fixed costs Acquiring and paying competent IT staff Competent is often very hard to get Buying and maintaining servers Correctly hosting hardware Proper power and cooling facilities, network connections, server racks, etc. Buying and maintaining software Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 7 Load and Utilization Issues How much hardware resources are required by each application and / or service? How to handle scaling issues? What happens if demand increases or declines? How to handle spike loads? Digg Effect Traditional data centers are notoriously underutilized, often idle 85% of the time Over provisioning for future growth or spikes Insufficient capacity planning and sizing Improper understanding of scalability requirements etc. Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 8 Cloud computing centrally unifies computation resources and provides them on-demand Degree of centralization and provision may differ Centralize hardware within a department? A company? A number of companies? Globally? Provide resources only oneself? To some partners? To anybody? How to compensate resource for resource usage? Provide resources by a rental model (e.g. monthly fee)? Provide resources metered on what-is-used basis (e.g. similar to electricity or water?) Provide resources for free? Usually, three types of clouds are distinguished Public Cloud Private Cloud Hybrid Cloud Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 9 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 10 Public Cloud Traditional cloud computing Services and resources are offered via the internet to anybody willing to pay for them User just pays for services, usually no acquisition, administration or maintenance of hardware / software necessary Services usually provided by off-site 3 rd party providers Open for use by general public Exist beyond firewall, fully hosted and managed by the vendor Customers are individuals, corporations and others e.g. Amazon's Web Services and Google AppEngine Offers startups and SMB s quick setup, scalability, flexibility and automated management. Pay as you go model helps startups to start small and go big Security and compliance? Reliability and privacy concerns hinder the adoption of cloud Amazon S3 services were down for 6 hours What will Amazon do with all the data? Private Cloud Cloud computing hardware are within the premises of a company behind the cooperate firewall Resources are only provided internally for various departments Private clouds are still fully bought, build, and maintained by the company using it But not by the single departments! Still, costs could be prohibitive and cost might exceed public clouds Fine grained control over resources More secure as they are internal to organization Schedule and reshuffle resources based on business demands Ideal for apps requiring tight security and regulatory concerns Development requires hardware investments and in-house expertise Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 11 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 12 2

3 Hybrid Cloud Both private and public cloud services or even non-cloud services are used or offered simultaneously State-of-art for most companies relying on cloud technology Properties promised by Cloud computing Agility Resources are quickly available when needed i.e. servers must not be ordered and build, software doesn t need to be configured and installed, etc. Costs Capital expenditure is converted to operational expenditure Independence Services are available everywhere and for any device Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 13 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 14 Multi-tenancy Resources are shared by larger pool of users Resources can be centralized which reduces the costs Load distribution of users differs Peak loads can usually be distributed Overall utilization and efficiency of resources is better Reliability Most cloud services promise durable and reliable resources due to distribution and replication Scalability If a user needs more resources or performance, it can easily provisioned Low maintenance Cloud services or applications are not installed on user s machines, but maintained centrally by specialized staff Transparency and metering Costs for computation resources are directly visible and transparent Pay-what-you-use models Cloud computing generally promises to be beneficial for fast growing startups, SMBs and enterprises alike. Cost effective solutions to key business demands Improved overall efficiency Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 15 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 16 The cloud heavily encourages a self-service model Users can just request the resources they need and use them Everything-as-a-Service In general, cloud providers of some computation resources as a service In the long run, all computation needs of a company should be modeled, provided and used as a service i.e. Amazon s private and public cloud infrastructures: everything is a service! from cloudscaling.com Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 17 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 18 3

4 Services provide a strictly defined functionality with certain guarantees Service description and service-level agreement (SLA) Services description explains what is offered by the service SLA further clarifies the provisioning guarantees Often: performance, latency, reliability, availability, etc. Usually, three main resources may be offered as a service Software as a Service Client SaaS Platform as a Service Application PaaS Infrastructure as a Service Platform IaaS Insfrastructure Server Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 19 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 20 Application Services (services on demand) Gmail, GoogleCalender Payroll, HR, CRM, etc Sugarm CRM, IBM Lotus Live Platform Services (resources on demand) Middleware, Intergation, Messaging, Information, connectivity etc Amazon AWS, Boomi, CastIron, Google Appengine Infrastructure as services (physical assets as services) IBM Blue House, VMWare Cloud Edition, Amazon EC2, Microsoft Azure Platform, Individuals Corporations Non-Commercial? CLOUD Cloud Middle Ware Storage OS Network Service(apps) SLA(monitor), Provisioning Provisioning Provisioning Provisioning Security, Billing, Payment Resources Services Storage Network OS Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 21 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 22 Infrastructure as a Service (IaaS) Provides raw computation infrastructure, i.e. usually a virtual server Successor to dedicated server rental For the user, a virtual server is similar to a real server Has CPU cores, main memory, hard disc space, etc. Usually provided as self-service raw machine User is responsible for installing and maintaining applications like e.g. operating system, databases or server software User does not need to buy, host or maintain the actual hardware The IaaS provider can host multiple virtual servers on a single, real machine Usually, virtual severs per real server Virtualization is used to abstract server hardware for virtual servers Virtual system also often called virtual machines (neutral term) or appliances (usually suggesting preinstalled OS and software) e.g. Cloudera appliance from exercise 12 Virtualization of hardware is usually handled by a socalled hypervisor, e.g. Xen, KVM, VMWare, HyperV, Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 23 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 24 4

5 1 #appliances many 7/16/2010 In short, IaaS is virtualization on multiple hardware machines Normal Server 1 machine with one OS Traditional virtualization 1 machine hosting multiple virtual servers Distributed Application 1 appliance running un multiple machines IaaS Multiple machines running multiple virtual servers Dynamic load balancing between machines Traditional virtualization Normal server IaaS Distributed Appliance 1 #machines many Hypervisor is responsible for allocating available resources to VMs Dispatch VMs to machines Relocate VM to balance load Distribute resources Network adaptors, logical discs, RAM, CPU cores, etc Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 25 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 26 Usually, virtual machines offered by IaaS infrastructures cannot grow arbitrarily big Usually capped by actual server size or a smaller server group Really big applications are usually deployed in so-called Pods Similar to database shards Group of machines running one or multiple appliances Machines within a Pod are very tightly networked i.e. each Pod is a full copy of given virtual machines with full OS and application installed Usually, there are multiple copies of a given Pod (and its VMs) Each Pod is responsible for a disjoint part of the whole workload Pods are usually scattered across availability zones (e.g. data centers or a certain rack) Physically separated, usually with own power / network, etc. IaaS Pods Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 27 from CloudScaling.com Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 28 Simplified Pod example: Googl Multiple Pods, each Pod running on multiple machines with a full and independent installation of Gmail software Load balancer decides during user log-in which Pod will handle the user session Users are distributed across Pods Pods are dynamic by using shared GFS file system Mission critical applications should be designed such that they run in multiple availability zones on multiple Pods Cloud control system (CCS) responsible for distribution and replication Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 29 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 30 5

6 Pod Architectures Each pod consists of multiple machines with mainboards, CPUs, and main memory Question: where to put secondary storage? Usually, three options Storage area network (SAN) Direct attached storage (DAS) Network attached storage (NAS) Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 31 SAN Pods Individual servers don t have own secondary storage Storage area network provides shared hard disks storage for all machines of a Pod Pro All machines have access to the same data Allows for dynamic load balancing or migration of appliances e.g. VMware vmotion Con Very very expensive Higher latency than direct attached storage Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 32 SAN Pods DAS Pods Each server has its own set of hard drives Accessing data from other servers may be difficult Pro Cheap Low latency for accessing local data Con Usually, no shared data access Usually, difficult to live-migrate appliances (due to no shared data) But: by using clever storage abstractions, common problem can be circumvented Use distributed file system or a distributed data store! e.g. Apache S3 & SimpleDB, Google GFS & BigTable, Apache HBase & HFS, etc. Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 33 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 34 DAS Pods IaaS example: Amazon EC2 Elastic Compute Cloud is one of the core service of the Amazon Cloud Infrastructure Public IaaS Cloud Customers may rent virtual servers hosted at Amazons Data Centers Can freely install OS and applications as needed Virtual servers are offered in different sizes and are paid by CPU usage Basic storage is offered within the VM, but usually additional storage services are used by application which cost extra e.g. S3 or SimpleDB Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 35 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 36 6

7 Example: Small EC2 VM 1.7 GB memory 1 EC2 Compute Unit (CU) 1 virtual core with 1 EC2 Compute Unit 1 CU is roughly a 1.2 GHz 2007 Xeon processor 160 GB instance storage (150 GB plus 10 GB root partition) 32-bit platform I/O Performance: Moderate Costs $0.095 per hour Usually most users start will the small instance, also heavily used for testing Example: Extra Large Instance EC2 VM 15 GB memory 8 EC2 Compute Units 4 virtual cores with 2 EC2 Compute Units each 1,690 GB instance storage GB plus 10 GB root partition 64-bit platform I/O Performance: High Costs $0.76 per hour Most cooperate users end with this instance due to higher IO speeds From July 2010 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 37 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 38 Example: High-Mem Quad XL EC2 VM 68.4 GB of memory 26 EC2 Compute Units 8 virtual cores with 3.25 EC2 Compute Units each 1690 GB of instance storage 64-bit platform I/O Performance: High Costs $2.68 per hour Largest standard instance Rough Estimations (Oct 2009) Roughly servers Uses standard server racks with 16 machines per rack Mostly packed with 2U dual-socket Quad-Core Intel Xeons Roughly matches the High-Mem Quad XL instance Uses around 8 500GB Raid-0 disks Target cost around $2500 per machine in average 75% of the machines are US, the remainder in Europe and Asia Amazon aims at a utilization rate of 75% Very rough guesses state that Amazon may earn $25,264 per hour with EC2! Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 39 From Oct 2009 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig PaaS 3.2 Google AppEngine Platform as a Service (PaaS) Provides software platforms on demand e.g. runtime engines (JavaVM,.Net Runtime, etc.), storage systems (distributed file system, or databases), web services, communication services, etc. PaaS systems are usually used to develop and host web applications or web services User applications run on the provided platform In contrast to IaaS, no installation and maintenance of operation system and server applications necessary Centrally managed and maintained Services or runtimes are directly usable Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 41 Google AppEngine provides users a managed Phyton or Java Runtime Web applications can be directly hosted in AppEngine Just upload you WAR file and you are done Users are billed by resource usage Some free resources provided everyday 1 GB in- and out traffic, 6.5 hours CPU, 500 MB storage overall Resource Unit Unit cost Outgoing Bandwidth GB $0.12 Incoming Bandwidth GB $0.10 CPU Time CPU hours $0.10 Stored Data GB / month $0.15 Recipients ed recipients $ Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 42 7

8 3.2 Google AppEngine 3.2 Amazon SimpleDB Each application can access system resources up to a fixed maximum AppEngine is not fully scalable! AppEngine max values CPU: 1730 hours CPU per day; 72 minutes CPU per minute Data in or out: 1 TB per day; 10 GB per minute Request: 43M web service calls per day, 30K calls per minute Data storage: no limit (uses BigTable which can scale in size!!) Amazon Simple DB is data storage system roughly similar to Google BigTable Simple table-centric database engine SimpleDB is directly ready to use No user configuration or administration Accessible via web service SimpleDB is highly available, uses flexible schemas, and eventual consistency Similar to HBase or BigTable Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 43 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig Amazon Simple DB Any application may use SimpleDB for data storage Simple web service provided to interact with Simple DB Create or delete a table (called domain) Put and delete rows Query for rows Users pay for storage, data transfer, and computation time 25 hours computation time (for querying) are free per month Later: $0.154 per machine hour 1 GB of data transfer is free per month Later: $0.15 per GB 1 Gb of data storage is free per month Later: $0.28 per GB 3.3 SaaS Software as a Service (SaaS) Full applications are offered on-demand User just need to consume the software; no installation or maintenance necessary All administrative and maintenance tasks are performed by the Cloud provider e.g. hosting physical hardware, maintaining platforms, maintaining software, dealing with security, scalability, etc. Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 45 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig SalesForce 3.3 SalesForce Salesforce.com On-Demand CRM software Customer-Relationship-Management Cooperation with Google Apps in early summer Provides simple online services for Customer database Lead management Call center Customer portal Knowledge Bases Collaboration environments Etc. Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 47 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 48 8

9 3.3 SalesForce 3.3 SalesForce Bills per month and user, based on edition Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 49 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig Google Apps 3.3 Google Apps Google Apps Provides standard office application on-demand i.e. Targeting at the lower-end of the customer base of Microsoft Office MS counter with Office Online Google Apps provides & Groupware Spreadsheets Documents Presentations Online Forms Drawings etc. Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 51 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 52 Next Semester Knowledge-Based Systems and Deductive Databases Data Warehousing and Data Mining Techniques Spatial Databases and Geographic Information Systems Seminar Best of Data Mining Distributed Data Management Thanks for your attention! Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 53 Distributed Data Management Wolf-Tilo Balke Christoph Lofi IfIS TU Braunschweig 54 9