11 Indranil Gupta (Indy) Lecture 4 Cloud Computing: Older Testbeds January 28, 2010 CS 525 Advanced Distributed Systems Spring 2010 All Slides © IG

2 Administrative Announcements Office Hours Changed from Today onwards: Tuesdays 2-3 pm (same as before) Thursdays 3-4 pm (new) My office 3112 SC

3 Administrative Announcements Student-led paper presentations (see instructions on website) Start from February 11th Groups of up to 2 students present each class, responsible for a set of 3 “Main Papers” on a topic –45 minute presentations (total) followed by discussion –Set up appointment with me to show slides by 5 pm day prior to presentation –Select your topic by Jan 31st List of papers is up on the website Each of the other students (non-presenters) expected to read the papers before class and turn in a one to two page review of the any two of the main set of papers (summary, comments, criticisms and possible future directions) – review and bring in hardcopy before class

4 Announcements (contd.) Projects Groups of 2 (need not be same as presentation groups) We’ll start detailed discussions “soon” (a few classes into the student-led presentations)

Timesharing Companies & Data Processing Industry 2010 Grids Peer to peer systems Clusters The first datacenters! PCs (not distributed!) Clouds and datacenters “A Cloudy History of Time” © IG 2010

6 Can there be a course devote to purely cloud computing that touches on only results within the last 5 years? –No! Since cloud computing is not completely new, where do we start learning about its basics? –From the beginning: distributed algorithms, peer to peer systems, sensor networks More Discussion Points

7 That’s what we do in CS525 Basics of Peer to Peer Systems –Read papers on Gnutella and Chord Basics of Sensor Networks –See links Basics of Distributed Algorithms Yeah! Let’s go to the basics.

8 Hmm, CCT and OpenCirrus are new. What about classical testbeds?

A community resource open to researchers in academia and industry Currently, 1077 nodes at 494 sites across the world Founded at Princeton University (led by Prof. Larry Peterson), but owned in a federated manner by 494 sites Node: Dedicated server that runs components of PlanetLab services. Site: A location, e.g., UIUC, that hosts a number of nodes. Sliver: Virtual division of each node. Currently, uses VMs, but it could also other technology. Needed for timesharing across users. Slice: A spatial cut-up of the PL nodes. Per user. A slice is a way of giving each user (Unix-shell like) access to a subset of PL machines, selected by the user. A slice consists of multiple slivers, one at each component node. Thus, PlanetLab allows you to run real world-wide experiments. Many services have been deployed atop it, used by millions (not just researchers): Application-level DNS services, Monitoring services, CDN services. If you need a PlanetLab account and slice for your CS525 experiment, let me know asap! There are a limited number of these available for CS All images © PlanetLab

Emulab A community resource open to researchers in academia and industry A cluster, with currently 475 nodes Founded and owned by University of Utah (led by Prof. Jay Lepreau) As a user, you can: –Grab a set of machines for your experiment –You get root-level (sudo) access to these machines –You can specify a network topology for your cluster (ns file format) Thus, you are not limited to only single-cluster experiments; you can emulate any topology Is Emulab a cloud? Is PlanetLab a cloud? If you need an Emulab account for your CS525 experiment, let me know asap! There are a limited number of these available for CS All images © Emulab

11 And then there were… Grids! What is it?

12 Example: Rapid Atmospheric Modeling System, ColoState U Hurricane Georges, 17 days in Sept 1998 –“RAMS modeled the mesoscale convective complex that dropped so much rain, in good agreement with recorded data” –Used 5 km spacing instead of the usual 10 km –Ran on 256+ processors Can one run such a program without access to a supercomputer?

13 Wisconsin MIT NCSA Distributed Computing Resources

14 An Application Coded by a Physicist Job 0 Job 2 Job 1 Job 3 Output files of Job 0 Input to Job 2 Output files of Job 2 Input to Job 3 Jobs 1 and 2 can be concurrent

15 An Application Coded by a Physicist Job 2 Output files of Job 0 Input to Job 2 Output files of Job 2 Input to Job 3 May take several hours/days 4 stages of a job Init Stage in Execute Stage out Publish Computation Intensive, so Massively Parallel Several GBs

16 Wisconsin MIT NCSA Job 0 Job 2Job 1 Job 3

17 Job 0 Job 2Job 1 Job 3 Wisconsin MIT Condor Protocol NCSA Globus Protocol

18 Job 0 Job 2 Job 1 Job 3 Wisconsin MIT NCSA Globus Protocol Internal structure of different sites invisible to Globus External Allocation & Scheduling Stage in & Stage out of Files

19 Job 0 Job 3 Wisconsin Condor Protocol Internal Allocation & Scheduling Monitoring Distribution and Publishing of Files

20 Tiered Architecture (OSI 7 layer- like) Resource discovery, replication, brokering High energy Physics apps Globus, Condor Workstations, LANs

21 The Grid Recently Some are 40Gbps links! (The TeraGrid links) “A parallel Internet”

22 Globus Alliance Alliance involves U. Illinois Chicago, Argonne National Laboratory, USC-ISI, U. Edinburgh, Swedish Center for Parallel Computers Activities : research, testbeds, software tools, applications Globus Toolkit (latest ver - GT3) “The Globus Toolkit includes software services and libraries for resource monitoring, discovery, and management, plus security and file management. Its latest version, GT3, is the first full-scale implementation of new Open Grid Services Architecture (OGSA).”

23 Some Things Grid Researchers Consider Important Single sign-on: collective job set should require once-only user authentication Mapping to local security mechanisms: some sites use Kerberos, others using Unix Delegation: credentials to access resources inherited by subcomputations, e.g., job 0 to job 1 Community authorization: e.g., third-party authentication For clouds, you need to additionally worry about failures, scale, on-demand nature, and so on.

24 Cloud computing vs. Grid computing: what are the differences? National Lambda Rail: hot in 2000s, funding pulled in 2009 What has happened to the Grid Computing Community? –See Open Cloud Consortium –See CCA conference (2008, 2009) Discussion Points

Backups 25

26 Normal No backup tasks 200 processes killed Sort Backup tasks reduce job completion time a lot! System deals well with failures M = R = 4000 Workload: byte records (modeled after TeraSort benchmark)

27 More Entire community, with multiple conferences, get-togethers (GGF), and projects Grid Projects: Grid Users: –Today: Core is the physics community (since the Grid originates from the GriPhyN project) –Tomorrow: biologists, large-scale computations (nug30 already)?

28 Grid History – 1990’s CASA network: linked 4 labs in California and New Mexico –Paul Messina: Massively parallel and vector supercomputers for computational chemistry, climate modeling, etc. Blanca: linked sites in the Midwest –Charlie Catlett, NCSA: multimedia digital libraries and remote visualization More testbeds in Germany & Europe than in the US I-way experiment: linked 11 experimental networks –Tom DeFanti, U. Illinois at Chicago and Rick Stevens, ANL:, for a week in Nov 1995, a national high-speed network infrastructure. 60 application demonstrations, from distributed computing to virtual reality collaboration. I-Soft: secure sign-on, etc.