Title: OGSA-DAI Usage Scenarios and Behaviour: Determining good practice
1OGSA-DAI Usage Scenarios and Behaviour
Determining good practice
- Mario Antonioletti
- mario_at_epcc.ed.ac.uk
- EPCC, University of Edinburgh
- http//www.ogsadai.org.uk
- AHM 2004, Data Services and Middleware, 2nd
September 2004
2OGSA-DAI
- OGSA-DAI is middleware
- Middleware should be invisible
- Provide additional functionality or hide
complexity - Allows uniform access to data resources
- data resources relational and XML databases,
files, - Provides an extensible framework
- You can extend functionality - fill any gaps
- We think it works well
- But need feedback
- Recount how OGSA-DAI is being used
- Some background first
3Basic Operational Model
DAISGR
Client
4Why OGSA-DAI?
- Why use OGSA-DAI over JDBC?
- Language independence at the client end
- Do not need to use Java
- Platform independence
- Do not have to worry about connection technology,
drivers, etc - Can handle XML resources
- Can embed additional functionality at the service
end - Transformations
- Third party delivery
- etc
- Avoiding unnecessary data movement
- Provision of Metadata is powerful
- Usefulness of the Registry for service discovery
- Dynamic service binding process
5More Complex Behaviour
GDS
And there's a lot more that you can do
6Usage Patterns
Retrieve
Update/Insert
Pipeline
Data Q - Query D - Delivery S - Status R -
Result U - Update I - Data id
7Activities are the drivers
- Express a task to be performed by a GDS
- Three broad classes of activities
- Statement
- Transformations
- Delivery
- Extensible
- Easy to add new functionality
- Does not require modification to the service
interface - Extension operate within the OGSA-DAI framework
- Functionality
- Implemented at the service
- Work where the data is (do not require to move
data back)
8OGSA-DAI Deck
9Building Applications
- Activities are grouped together
- Perform document
- Data can flow between activities
- Optimisation
- Avoids multiple message exchanges
- Can deliver to other GDSs
- Prerequisite for data integration
- Base middleware for projects requiring data
access - Some capability for data integration
- That is the theory now for the practice
- OGSA-DAI being adopted by a number of projects
10Who is Using OGSA-DAI?
N2Grid (http//www.cs.univie.ac.at/institute/index
.html?project-8080)
Bridges (http//www.brc.dcs.gla.ac.uk/projects/bri
dges/)
BioSimGrid (http//www.biosimgrid.org/)
INWA (http//www.epcc.ed.ac.uk/projects/inwa/)
BioGrid (http//www.biogrid.jp/)
AstroGrid (http//www.astrogrid.org/)
eDiaMoND (http//www.ediamond.ox.ac.uk/)
OGSA-DAI (http//www.ogsadai.org.uk)
GEON (http//www.geongrid.org/)
myGrid (http//www.mygrid.org.uk/)
MCS (http//www.isi.edu/deelman/MCS/)
ODD-Genes (http//www.epcc.ed.ac.uk/oddgenes/)
OGSA-WebDB (http//www.gtrc.aist.go.jp/dbgrid/)
GridMiner (http//www.gridminer.org/)
FirstDig (http//www.epcc.ed.ac.uk/firstdig/)
GeneGrid (http//www.qub.ac.uk/escience/projects.p
hpgenegrid)
IU RGRBench (http//www.cs.indiana.edu/plale/proj
ects/RGR/OGSA-DAI.html)
11Project classification
12Projects using OGSA-DAI
- These projects form a list of case studies
- Need to capture requirements
- How OGSA-DAI is being used
- Where it succeeds and where it fails
- Other issues that arise
- An on-going process
- Only time to outline salient points from a couple
of projects - More detail in the paper
- but this only gives a top level overview
- On-going process
- Solicit more
- If you have more then please get in touch
13- e-Digital MammOgraphy National Database
- Built a prototype of a national database of
mammographic images in support of the UK Breast
screening programme - Employ Grid technologies to facilitate this
process - Mike Brady gave a keynote that went over the
details
14(No Transcript)
15- eDiaMoND Findings
- OGSA-DAI provides a flexible framework
- Dynamically configure the system through
discovery - Activities can operate with different levels of
granularity - Federation can introduced at various levels
- Upgrading from R3 ? R4 broke some things
- Low level XML issues
- Good documentation on how to extend the framework
- Extended Activities to access IBM DB2 Content
Manager
16INWA Objectives
- Innovation Node Western Australia
- Informing Business Regional Policy
Grid-enabled fusion of global data and local
knowledge - Project
- Run from Nov 2003 - Aug 2004
- Involved 10 partners (6 UK 4 Australia)
- Aim
- Data mine commercially sensitive data
- Security an absolute MUST
- Employ Grid technologies
- Need access to data and computational resources
- Demonstrator using
- OGSA-DAI
- Incorporate data resources
- Sun DCG's TOG (Transfer-queue Over Globus)
- Handle job submission to analyse micro array data
17INWA
18INWA Lessons Learned
- Performing Data Integration
- TimeZone date problems
- Security issues
- Bugs in
- JavaCoG in GT3
- OGSA-DAI could not switch security for Grid data
transfers - TOG had no security option
- All of these have been fixed
- Middleware not mature enough for commercial
deployment
19ODD-Genes
- OGSA-DAI Demo for Genetics
- Collaboration between
- EPCC
- Scottish Centre for Genomic Technology and
Informatics (GTI) - Human Genetics Unit (HGU)
- ODD-Genes demonstrates
- Perform high-speed batch analysis of microarray
data on the Grid - Browse the results of previous analyses stored in
a database - View data from arbitrary databases as HTML
- Discover related databases on the Grid
- Perform coupled queries on newly-discovered
databases to provide a richer analysis of gene
data
20ODD-Genes Actors
1. Client 2. EPCC is an example of a
computational resource. 3. HGU is an example
of a data repository.
21ODD-Genes Findings
- Data discovery perceived to be very important
- Map data views time -gt spatial locations
- Discovery of new resources
- Transparency to data access
- _at_HGU had an XML database
- _at_GTI had a relational database
- Deploy OGSA-DAI and not worry about databases
- Issues
- Registry maintenance policy
- Semantics of the discovery process
- Groups working the same area but different
schemas, no generic metadata (schemas were the
effective metadata) - Provides an additional tool for researchers
22Other Projects
- AstroGrid
- Identified (and fixed) a number of bugs
- Passed on requirements
- FirstDig
- Identified a number of bugs
- Have contributed a data browser to OGSA-DAI
- GeneGrid
- Interfacing Perl through an OGSA-DAI service to
access biological databases - Requirement for file support
- EdSkyQuery-G
- Collaboration between OGSA-DAI Eldas
- Based on SkyQuery project by John Hopkins
University, Baltimore, USA
23More on Projects
- MSc at Edinburgh looking at data integration
scenarios - Benchmarking OGSA-DAI
- Investigating capabilities
- GDSActivity allowing perform documents to be
executed at other GDSs - Identifying further requirements for data
integration - control flow - sequence
- flow
- Question as to whether such capabilities should
be included in OGSA-DAI or OGSA-DAI should
interface with other workflow languages - MSc at Edinburgh looking at C bindings to the
OGSA-DAI CTK - For language independance need to provide more of
these - Perl, Python Eiffel!!
- GridMiner
- Have a really cute logo
- Have a member of that team currently at NeSC
24Conclusions
- Still early days
- Standardisation process not stabilising quickly
enough - Infrastructure still developing and prone to
change - OGSA-DAI acting as an enabler
- Showing people what can be done
- However is it cracking a nut with a sledge
hammer? - Usage patterns are similar
- Call for people to work together to solve similar
problems - Problems that are not OGSA-DAI specific
- Metadata, Time zones, security,
- Data discovery perceived to be important
- Is this in the scope of what OGSA-DAI should be
doing? - Need to talk to users and gather war stories
- http//www.ogsadai.org.uk/projects
- On going process
25Further Information
- The OGSA-DAI Project Site
- http//www.ogsadai.org.uk
- The DAIS-WG site
- http//cs.man.ac.uk/grid-db
- OGSA-DAI Users Mailing list
- users_at_ogsadai.org.uk
- General discussion on grid DAI matters
- Formal support for OGSA-DAI releases
- http//www.ogsadai.org.uk/support
- support_at_ogsadai.org.uk
- OGSA-DAI training courses