Introduction to PaaS and IaaS Cloud Computing. Roberto Beraldi

Transcription

1 Introduction to PaaS and IaaS Cloud Computing Roberto Beraldi

2 Models for Cloud Computing (SaaS)Software as a Service XaaS (PaaS) Platform as a Service (IaaS) Infrastructure as a Service

3 Modelsfor cloudcomputing

4 CC in a nutshell Cloud computing is a way to use Information Technology infrastructures without the need to install specific HW related to the infrastructures being used. IT infrastructure can be as simple as a single raw virtual machine, more abstract as a swplatformused to develop and running applications on several machines, or a sw application

5 What CC can provide? Infrastructure Platform Software API STorage X as a service(iaas) as a service(paas) as a service(saas) as a service(apiaas) as a service(staas) as a service (XaaS)

6 Main characteristics of CC Pay-per-use no ongoing commitment, utility prices Elastic capacity and the illusion of infinite resources Multitentancy Same instance of an application to serve multiple clients Resources that are abstracted or virtualized Resources provided as a Service and with a self-service Interface provides users the ability to upload, build, deploy, schedule, manage, and report on their business services on demand.

7 Factors enabling cloud computing Hardware HW virtualization Multi-core chips Distributed Computing Utility computing Grid Computing.. Cloud computing Web 2.0 Web Services Mashups SoA Internet Technologies Autonomic Computing Data Center Automation System Management

8 Cloud actors

9 Platformasa Service A cloud platform offering an environment on which developers create and deploy applications E.g., decide the size of the VM, where they are located, etc. Different Programming Languages PHP Java Ruby Different DB Web based console to create application (with dashboard)

10 Platformasa Service Developers can use an IDE to develop the application and use either an SDK or CLI to deploy the application Impact on the programming model Main players: Google s app engine, OpenShift, Windows Azure, and many more

11 PaaS example: GAE Cloud service for running web applications on the Google data center GAE isoneof the mostinterestingand complete PaaS Simple configuration Transparent scalability infinite number of applications, req/sec storage Security All applications run inside a sandbox, do not have direct access to file system, cannot open other connections Different programming languages

12 GAE console

13 Compute App Engine VM Storage BigTable SQL Datastore Operations Monitoring Debugging Etc. Tools Deployment Manager Development Big Data Lots of service

14 SDK

15 GAE architecture Google App Engine speaks with web applications through the Web Server Gateway Interface(WSGI) standard protocol App Engine and SDK includes the webapp2 framework that implements WSGI WSGI Protocol HTTP Requests WEB Server WEB App

16 GAE: supported language Java JVM, Java servlet, SDK Eclipse extension Python Standard library (without unsecure calls) Go PHP (new)

17 LAB: Hello Word in GAE What we need: Google account GAE registration Plafond free (10 app) Register a new application The application ID will be used to deploy the application SDK Use the language Python 2.7 (no support for 3.x)

18 Hello Word in GAE Step 1 Code helloworld.py Deploy Step 4 Google Cloud Web-based Admin console Conf app.yamlstep 3 Simulator Step 2

19 Hello Word in GAE Step 1 Code helloworld.py Define a handler for the HTTP requests as a class that extends webapp2.requesthandler class (MainPage) Attributes : response, request(instance of class Request, Response) Methods: get,post, etc.. (to override) Map HTTP get request to get method (also post, put, etc..) Write data to HTTP response through self.response appis a global name that must assigned to the application

20 Step 3 Conf app.yaml Deploy Step 4 Google Cloud appcfg.py update. Web-based Admin console An applicationnamehellowordmust be registeredwith the google engine helloworld.appspot.com

21 Dashboard

22 GAE architecture (simplified view) HTTP Requests App Eng Front End App Eng Front End App Eng Front End Load Balancer App Server App Server App Server Other Google Service API layer APP APP APP

23 Python GAE architecture REQ/REP Services CGI Sandbox URLfetch mail images Python VM Standard Lib App Read-only File system BigTable MEMCACHE DATASTORE Source: Google App Engine Guido van Rossum

24 Python GAE architecture (scaling) REQ/REP Services CGI Sandbox URLfetch mail images.. Python VM Standard Lib App Read-only File system BigTable MEMCACHE DATASTORE Source: Google App Engine Guido van Rossum

25 Example: PHP an app that handles customer requests might include separate modules to handle other tasks, such as: API requests from mobile devices Internal, admin-like requests Backend processing such as billing pipelines and data analysis

26 Appicationmodulesinstances

27 GAE and mobile apps

28 OpenShift OpenShiftOnlineby RedHat is a Platform as a Service (PaaS) that provides developers and IT organizations with an auto-scaling, cloud application platform for deploying new applications on secure, scalable resources with minimal configuration and management overhead. Languages Java, Ruby, and PHP. Integrated developer tools, such as Eclipse integration, JBossDeveloper Studio, and Jenkins, support the application life cycle. Database MySQL, PostgreSQL, MongoDB, and SQLite. OpenShiftOnlineprovides disk space, CPU resources, memory, network connectivity, and an ApacheorJBossserver to create, deploy, and manage applications in the cloud. Management web console CLI, very powerful for coding debugging etc Source: online documentation

29 OpenShift: basicsystem components

30 Subscriptionplan

31 Example: create and application gittopull CLIENT git commit GEAR

32 PaaSexample2: Windows Azure It is a set of integrated cloud technologies each providing a specific set of services to application developers Windows Azure provides developer-accessible services for creating applications Strongly integrated with Visual studio Development fabric simulator Development storage simulator

33 Windows azure Two execution models for applications Web hosting: Web Site PaaS: Cloud Service IaaS: Virtual Machines

34 Deployement 1. Register (Live-id) Web Portal 2. Create Hosted-Service 3. Package upload.csconf +.cspkg Service Service Conf (n.inst. =3) Fabric Controller Service Service.cspkg

35 Microsoft azure Lots of services are added during the years Computation VM,Cloud Services,Batch,RemoteApp Web and mobile device Backend for mobile app Data and storage Data analysis Machine learning Internet of Things

36 INFRASTRUCTURE AS A SERVICE

37 Cloud computing in a nutshell (by an analogy) Production Distribution Utilization Electricity is virtual entity (many sources, we do not care from where we receive it, ) Pay-as-you-go Elastic

38 CC: Virtual computing power Provider Utilization CPU cycles Memory Storage Virtual machine control panel User decides the size on the VM

39 IaaS A cloudinfrastructureenables on-demand provisioning of servers running several choices of operating systems and a customized software stack. Cloud computing services are usually backed by large-scale data centerscomposed of thousands of computers. Such data centers are built to serve many users and host many disparate applications. Offers virtualizedresources (computation, storage, and communication) on demand

40 IaaS: deployment models

41 Virtualization, main idea Memory: Virtual Memory (>=Physical memory) Multitasking: Several processes concurrently on the same HW, see the same ISA. HW is shared thanks to an OS than manages critical instructions. Virtual Machine: 60 from IBM on mainframes Abandoned with the advent of PCs, now again used for cloud computing Even different ISA on the same CPU Used to run different OS (not processes) Achieved through a Virtual Machine Monitor

42 Isolation Through virtualization, workload isolationis achieved since all program instructions are fully confined inside a VM, which leads to improvements in security. Betterreliability is also achieved because software failures inside one VM do not affect others. Moreover, better performance control is attained since execution of one VM should not affect the performance of another VM.

43 Isolation

44 Application mobility Workload migration, also referred to as application mobility, targets at facilitating hardware maintenance, load balancing, fault tolerance and disaster recovery. It is done by encapsulating a guest OS state within a VM and allowing it to be suspended, fully serialized, migrated to a different platform, and resumed immediately or preserved to be restored at a later date. A VM s state includes a full disk or partition image, configuration files, and an image of its RAM.

45 Application mobility

46 HW consolidation Virtualization makes it possible to consolidate individual workloads onto a single physical platform, reducing the total cost of ownership.

47 Interface of a computing system

48 Virtual Machine Virtual Machine is a logic machine (M L ) whose ISA is implemented exploiting software running on a physical machine (M F ) Two main types: Native. M L =M F Same ISA. Indeed instructions of the M F are in large part executed on the real CPU. Sensitive instruction are trapped. Emulation M L M F (different ISA) HW emulation Language level emulation (java)

49 Emulation HW emulation: ISA is different from real CPU Sparc emulates IA32 Installation of different OS Language specific VM JVM CLR

50 Native emulationvirtual machine Same machine as the physicalmachine Efficient, isolated duplicate of a real machine ) Virtualization is realized by a Virtual Machine Monitor (VMM) o hypervisor

51 Full virtualization Native emulation OS without modification (e.g., VMWare s ESX, ESXi) OS legacy Para virtualization OS must be modified (e.g., Open source s XEN) Higher efficiency

52 Resources Xenand the Art of Virtualization, Pratt et al. SOSP The Architecture of Virtual Machines, Smith, J.E.; R. Nair, IEEE Computer, May 2005, Volume: 38, Issue: 5 A Comparison of Software and Hardware Techniques for x86 Virtualization, K. Adams, O. Agesen. ASPLOS 2006.

53 Classical virtualization A classical VMM executes guest operating system directly, but at a reducedprivilegedlevel. The VMM intercepts traps from the de-privileged guest, and emulates the trapping instruction against a virtual machine state [*] [*] A camparisonof Software and Hardware Techniques for x86 Virtualization, K.Adams, O.Agesen, ASPLOS 2006

54 Classicalvirtualization, esempio a. CPU executes a kernel instruction of the Guest OS while being in user mode b. CPU generates a trap c. Control passes to the VMM that emulates the instruction d. 2 is different of 2, but is produces the same effect ( (for example, CLIVCPU.IF=0) User level Guest OS trap Kernel level VMM 2 Not privileged instruction Privileged instruction e.g.. CLI, Clear Interrupts green= User Mode red= System Mode 5 time

55 Hwvirtualizazion Hardware virtualization allows running multiple operating systems and software stacks on a single physical platform. The virtual machine monitor (VMM), hypervisor, mediates access to the physical hardware presenting to each guest operating system a virtual machine (VM), which is a set of virtual platform interfaces

56 Type-1 hypervisor(bare metal) Guest OS runs unchanged Used to build a Hardware Server (cloud computing) Hyper-V(Microsoft), VMWare s ESX

57 Type-2 hypervisor(hosted) Runs on top of a Hosting OS Often used on clients

58 Example of VMM: Virtual Box It usually runs on Desktop computers VMM runs as an application hosted by an OS Lower performance, easy to install VM

59 HW assistedvirtualization Processors are designed to help virtualization For example, Intel-VT and AMD-V provide additional instructions that help virtualization Hypervisorscan use theseinstructionsto improvethe performance Linux KVM, Microsoft Hyper-V, Microsoft Virtual PC, Xen, etc. use these features

60 IaaSprovider spoint of view A key challenge IaaSproviders face when building a cloud infrastructure is managing physical and virtual resources, namely servers, storage, and networks, in a holistic fashion. The orchestration of resources must be performed in a way to rapidly and dynamically provision resources to applications.

61 IaaSprovider spoint of view The software toolkit responsible for this orchestration is called a virtual infrastructure manager (VIM). This type of software resembles a traditional operating system ( cloud operating system ) but instead of dealing with a single computer, it aggregates resources from multiple computers, presenting a uniform view to user and applications.

62 VIM and hypervisor Virtual server Hypervisor Hypervisor Hypervisor VIM Virtualization platform physical servers

63 Automatedscaling Physical server 1 Physical server 2 2) VIM allocatesthe newvm hypervisor 2 VIM hypervisor Automated scale listener 4 3) User increases the load request 3 1 Usage and administrator portal 1)Userrequesta newvm Thatjoinsthe existing3 VM

64 Example: automatedscaling Physical server 1 Physical server 2 hypervisor VIM hypervisor Automated scale listener

65 Example: OpenNebula Interface to Public Clouds: it offers a driver to manage the life cycle of virtualized resources obtained from external cloud providers. In case of spikes in demand, extra load can be offloaded to rented resources. To the applications, the use of leased resources must ideally be transparent

66 Example: OpenStack OpenStackis a cloud operating system that controls large pools of compute, storage, and networking resources throughout a datacenter, all managed through a dashboard that gives administrators control while empowering their users to provision resources through a web interface.

67 Example of IaaS Windows azure Different machine with different size and OS Different geographical region where the machine is located Free trial (requires registration with VISA)

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73 MainAmazon Web Service offering Elastic Cloud Computing (EC2) Amazon Elastic Compute Cloud (Amazon EC2) is a web service that provides resizable compute capacity in the cloud. Amazon Simple Storage Service (Amazon S3) Amazon S3 provides a simple web services interface that can be used to store and retrieve any amount of data, at any time, from anywhere on the web. Amazon Simple Queue Service (Amazon SQS) offers a reliable, highly scalable hosted queue for storing messages as they travel between computers

74 Currentoffer

75 Amazon Web Services (EC2) Rich set of VM General purpose baseline level of CPU performance with the ability to burst above the baseline Compute Optimized, GPU, etc Reserved Instance Amazon EC2 Reserved Instances allow to reserve Amazon EC2 computing capacity for 1 or 3 years Dedicated Instance run in a VPC (Virtual Private Cloud) on hardware that's dedicated to a single customer. Cluster networking Spot Instance allow to bid on spare Amazon EC2 computing capacity.

76 Price (dependson the location)

77 Microsoft Azure vs Amazon AWS Short story: AWS is superior to Windows Azure Long story: see

78 New trends: Containers Each virtual machine includes the application, the necessary binaries and libraries and an entire guest operating system -all of which may be tens of GBs in size.

79 Containers Containers include the application and all of its dependencies, but share the kernel with other containers. They run as an isolated process in userspaceon the host operating system. Same OS! Runs only on Linux Much faster

80 Mobile Cloud Computing Exploiting cloud approach to boost the performance of an application, reduce the energy consumption, increase the computation power Example: CloneCloud The system is a flexible application partitionerand execution runtime that enables unmodified mobile applications running in an application-level virtual machine to seamlessly off-load part of their execution from mobile devices onto device clones operating in a computational cloud.

81 CloneCloud: main idea

82 Mobile-to-mobile offloading

83 Questions?