1. The XCAT Science Portal
Sriram Krishnan, et al
Extreme! Computing Lab, Indiana University
Jay Alameda
National Computational Science Alliance
Richard Alkire, et al
Department of Chemical Engineering
University of Illinois, Urbana-Champaign
11/28/2018
Extreme! Lab, Indiana University

2. Extreme! Lab, Indiana University
Outline
Existing Portals
Motivating Factors
Prototypical Architecture
Sample Applications
Summary
11/28/2018
Extreme! Lab, Indiana University

3. Extreme! Lab, Indiana University
Existing Portals
User Portals
Simple Job Submission & Tracking, File Management, Resource Selection
NPACI Hot Page, Unicore, Nimrod-G, NCSA User Portal…
Science Portals
Application Specific Environment for orchestrating complex scientific tasks involving remote resources
Cactus, ECCE/ELN, Lattice, Gateway, Discover
Portal Construction Kits
APIs needed for a Portal to communicate with a Distributed Set of Resources
CoG, GPDK, JiPANG, Grid Port
Cactus : Black Hole, Al Einstein Inst, ECCE/ELN : ORNL, LBL, PNNL – Computational Chem Engineering
Lattice : High Energy Physics – Jefferson Labs. Gateway/Discover : CORBA
11/28/2018
Extreme! Lab, Indiana University

4. Motivation for Our Effort
Need a Generic mechanism to control Applications for the Grid
Grid : Set of distributed services and protocols that have been deployed across a large set of resources
Use Scripts!
Need a simple and efficient mechanism to
Encapsulate data specific to each application
Share such encapsulated data with peers
Use the Active Document model to work for scientific applications
Active Document: A Notebook containing
pages of text & graphics describing the application
pages of parameterized executable scripts
Services : authentication, authorization, security, namespaces, file/object management, events, resource co-scheduling, user services, network QoS, information/directory services
What’s wrong with other portals – too specific to each application, ours will be generic (using scripts)
11/28/2018
Extreme! Lab, Indiana University

5. Other Motivating Factors
Easy Web based Access to the Grid
Application Domain Knowledge in terms of Application Science
Communication with Remote Applications
Use an Event System
Resource Utilization Information
Use a Grid Performance Monitor
Activeness of Active Documents, Ease for sharing with peers, self sufficient, can be run
11/28/2018
Extreme! Lab, Indiana University

6. Simplified Portal Architecture
User’s Workstation
Portal Web Server
The Portal
Authentication
& Authorization
Script
Engine
Notebook
Database
The Grid
I will expand on the boxes in blue in future slides
Grid
Performance
Monitoring
Event
Channel
Application
Manager
Application
Manager
11/28/2018
Extreme! Lab, Indiana University

7. Scripting Computations
Portal Scripts are Grid Enabled
Scripting Language : Jython
Globus CoG API used to access the grid
Access to the XCAT Distributed Component System via the CCA Jython API
CCA : The DOE Common Component Architecture
XCAT : Extreme Lab implementation of the CCA Specification, built currently on top of XSOAP
Globus : Argonne National Lab
Need a simplified overview picture before this
11/28/2018
Extreme! Lab, Indiana University

8. Snapshot of Script Editor
Notebook Script
Edit Window
-Allows User to
modify details
of Grid Execution
Control flow
11/28/2018
Extreme! Lab, Indiana University

9. Forms Based User Interface
Notebook
Browsing
Controls
Notebook Scripts
can be
“parameterized”
by web forms
Page
Selection
Tree
11/28/2018
Extreme! Lab, Indiana University

10. XCAT Application Managers
Manage non grid aware applications
Stage files
Monitor Status
Send Events
Communicate using XSOAP
Launched on the Grid by Portal scripts
Combine advantages of
Remote Object, invoked via well defined interfaces
Remote Shell
Functionality defined by Jython scripts
11/28/2018
Extreme! Lab, Indiana University

11. XCAT Application Managers…
Application Managers can dynamically sprout interfaces (CCA Ports) to communicate with other similar CCA components. Applications can be c, c++, Fortran, anything.
11/28/2018
Extreme! Lab, Indiana University

12. Extreme! Lab, Indiana University
Event Subsystem
Events for communication between the portal and the remote jobs
Implemented over XSOAP
SOAP : Simple Object Access Protocol
Network Protocol : HTTP
Wire Protocol : SOAP1.1
Events can be published by Java, C++, C and Jython applications
Apps can write preformatted XML strings to a socket to send events
Wire Protocol = Transfer Syntax
11/28/2018
Extreme! Lab, Indiana University

13. Event Subsystem : Continued
XCAT Portal
Event Channel
Subscribe
Jython
Script
Receive Events
Publish Events
Remote Job
Job Launch
Applications publish events to channel, which provides type based filtering. Dynamically added Jython subscribers subscribe to application specific events
Grid Aware Applications /
XCAT Application Managers
User’s Workstation
The Grid
11/28/2018
Extreme! Lab, Indiana University

14. Grid Performance Monitor
Visualization of resources, current and predicted future loads (using NWS)
Built using the XSOAP based Event Subsystem
Java Swing Based Visualization
Machine
Sensor
Resource Utilization Events
Receive Resource Events
Machine
Sensor
To be used as a resource recommender
Event Channel
Visualizer
Machine
Sensor
Subscribe
11/28/2018
Extreme! Lab, Indiana University

15. Extreme! Lab, Indiana University
The Notebook Database
Stores the Notebook corresponding to each application
Currently built on top of the underlying directory structure of the file system
Metadata about Notebooks stored in XML
Notebooks can be Exported (published), and Imported (retrieved) to/from web based repositories
Each notebook is stored as a directory, each page is a subdirectory. Notebooks contain web pages and scripts, among other things.
Notebook : per experiment/per project/… discussion
11/28/2018
Extreme! Lab, Indiana University

16. The Notebook Database…
Notebook Server
Database Interface
Notebook 1
Notebook 2
Notebook 3
Script
Script
Page 1
Page 2
Page 1
Page 2
Page
11/28/2018
Extreme! Lab, Indiana University

17. Security & Authentication
Authentication : Grid Security Infrastructure (GSI) via the CoG Toolkit
GSI : Based on Public Key Encryption, X.509 Certificates and SSL
Authorization
Personal Mode : Only the owner is authorized
Multi User Mode : Under Construction!
Security : XSOAP using SSL & GSI
Under Construction!
Some of the work is in progress
11/28/2018
Extreme! Lab, Indiana University

18. Portal Architecture : Summary
Current Implementation is of the personal mode, where the server runs on each user’s machine, and is on a per user basis. Theoretically, the user can use not only the browser, but also other tools to communicate with it via other protocols
11/28/2018
Extreme! Lab, Indiana University

19. Extreme! Lab, Indiana University
Sample Application : 1
NCSA Chemical Engineering Team
Semiconductor Processing
Copper Electro Deposition on Silicon
Optimizing Semiconductor Fabrication Processes
The Problem
Engineer at company X wants to simulate changes in chip fabrication by changing process parameters
To accomplish this two different simulations needed to be coupled
Trench forms the interconnect on microprocessor chips.
Continuum model of diffusion processes in the deposition bath adjacent to the trench.
Monte Carlo model of events that occur in the near surface region where solution additives influence the evolution of deposit shape and roughness during filling of the trench.
11/28/2018
Extreme! Lab, Indiana University

20. The Problem in Greater Depth
It is a Grid problem
The Monte Carlo simulation is at University Y
The Continuum simulation is at Company Z
The effort must protect security for each peer
Codes may be used but not moved
Data must be protected
How does Engineer at X do this?
Engineer’s Grid Script
1 Launch MC at Y
2. Launch Cont at Z
3. Link MC to Cont
4. Execute MC & Cont
5. Store results at X
NCSA
This is a scientific
notebook example
there is text and
there is also some
interesting graphics
and some scripts X Z Y
The Grid

21. Extreme! Lab, Indiana University
The Big Picture…
Portal (X)
The Grid
Application
Manager (Y)
Application
Manager (Z)
XCAT Application Managers for the non grid aware codes
File Transfer using Grid based File Management Utilities
Monte Carlo
Simulation
Continuum
Simulation
Grid File
Management
Data
File
Data
File
11/28/2018
Extreme! Lab, Indiana University

22. Snapshot of User Interface
Parameter Form for the Chemical Engineers
11/28/2018
Extreme! Lab, Indiana University

23. Extreme! Lab, Indiana University
Sample Application: 2
Tracking Space Junk
Approximately 9,000 objects larger than 3 cm orbiting earth with speeds averaging about 10 Km/sec
The Problem:
To maneuver satellites you need to know if you will hit the space junk
Must predict thousands of orbit paths
Embarrassingly Parallel
Use of the Portal to parameterize the computation
11/28/2018
Extreme! Lab, Indiana University

24. Extreme! Lab, Indiana University
More Details…
The Algorithm
Divide objects into groups of size < 100
Send each group to a remote machine to compute orbit trajectories
Report potential collisions back to the local Visualizer
Use of Grid Aware XCAT Components
Inside the
Portal
Orbit
Calculator
Orbit
Calculator
Orbit
calculator
This is a scientific
notebook example
there is text and
there is also some
interesting graphics
and some scripts
Orbit
Calculator
Orbit
Calculator
Master /
Visualizer
Orbit
Calculator
11/28/2018
Extreme! Lab, Indiana University 3

25. Extreme! Lab, Indiana University
Summary
A generic programming tool for grid application designers
Scripting of complex applications
A simple forms based web browser interface to these applications
An effective use of the Active Document model to package applications, and share them with others
A grid event system integrated into grid applications and resource monitoring
A distributed software component model (viz. DOE CCA) used as an effective tool to manage distributed applications
Benefits should be clearer, contributions.
Probably need a future directions slide
11/28/2018
Extreme! Lab, Indiana University