Trilinos Strategic (and Tactical) Planning

Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company,for the United States Department of Energy under contract DE-AC04-94AL85000.

Outline of Talk

Strategic Goals. Future Trilinos Presentations. Decisions: Made, pending, emerging. Brainstorming.

Trilinos Strategic Goals Scalable Computations: As problem size and processor counts

increase, the cost of the computation will remain nearly fixed.   Hardened Computations: Never fail unless problem essentially

intractable, in which case we diagnose and inform the user why the problem fails and provide a reliable measure of error.

Full Vertical Coverage: Provide leading edge enabling technologies through the entire technical application software stack: from problem construction, solution, analysis to optimization.

Grand Universal Interoperability: All Trilinos packages will be interoperable, so that any combination of packages that makes sense algorithmically will be possible within Trilinos and with compatible external software. 

Universal Accessibility: All Trilinos capabilities will be available to users of major computing environments: C++, Fortran, Python and the Web, and from the desktop to the latest scalable systems.

Universal Solver RAS: Trilinos will be: Integrated into every major application at Sandia (Availability). The leading edge hardened, efficient, scalable solution for each of these

applications (Reliability). Easy to maintain and upgrade within the application environment

(Serviceability).

AlgorithmicGoals

SoftwareGoals

Trilinos Presentation Forums

HPCSW Workshop Tutorial High Performance Computer Science Week (HPCSW) Successor to LACSI Symposium. March 31 – April 4, 2008, Denver.

ACTS “Hands-on” Tutorial: Aug 19-21, 2008 (approximate). At Lawrence Berkeley Lab, Berkeley, CA, USA.

Next Trilinos User Group Meeting: Proposal: Oct 21-23, 2008. Old LACSI Symposium week. At Sandia National Laboratories, Albuquerque, NM, USA.

SciDAC Conference (tentative). July13-17, 2008. Seattle.

SC2008 Tutorial?

Decisions Made: Scope Trilinos scope is larger: capabilities, customers, platforms. Capabilities key descriptors: When is a package appropriate for Trilinos?

Embeddable, reusable, interoperable. Scientific/engineering. Not applications (but probably app components in the future). Others?

Customers: NNSA, DOE Office of Science. DoD, DHS, general WFO. Broader community.

Platforms: All Oses: Unix/Linux, Windows, Mac Standard command line, Visual Studio, Xcode. Goal: Downloadable self-extracting archives. Cmake is the ticket.

Decisions Pending: Aggregation

40+ packages: Aggregation necessary in some way. Miller’s Law: 7 +/- 2. How to aggregate?

Already some: Epetra_Operator/RowMatrix. Thyra operators evaluators. Stratimikos.

How do we build on this? No reason to introduce hierarchy in repository. Aggregation in:

• Concept, documentation, packaging.

Big question: What gets put together? Proposal: Start with Stratimikos-related packages?

Decisions Emerging: TDD

Rigor alternative? TDD Steps:

1. Write the test.2. Test and prove it failed.3. Write code.4. Prove test passed.

Test-driven development. How? Make test registration easier.

Inspections: Higher priority. How do we facilitate? Actions:

• Develop checklist for closing bug review:– Code review, confirm that test checked.– Second person signs off on bug.

• Add item to release checklist asking if code was reviewed.

Decisions Emerging: Others

Source management: Continue looking at options. M. Eldred brings up good arguments for SVN.

Trilinos Advisory Group: Group of Trilinos technical stakeholders. Quarterly phone meetings. Communication of framework related issues. Meant to communicate and avoid misunderstandings:

• SIERRA BJAM decision.

• If TAG around, could have avoided a lot of confusing discussion.

Risks: Infrastructure staffing

Loss of (and risk of loss of) critical skill sets: Mike Phenow plans to leave at the end of January. Present staffing model for infrastructure is weak, unattractive. Staffing for support is less than 2 years ago (1.5 vs. 2), size of

project much larger.

Working toward a matrixed solution. ID’ed an additional role: scientific programmer.

Brainstorming

What’s missing from the vertical software stack? Goal: Build an application using Trilinos building blocks. Only the physics or similar is unique. Andy’s list. Tools for AtC interaction: Helgi Adelsteinssen, RichL. Mike Parks, Greg

Wagner, Kevin Long.

Interaction with UQ efforts (John Red-Horse). Builds from an app perspective. Other topics? Performance and scalability:

Can apps use Trilinos to get performance beyond previous capabilities? Performance benchmarks in apps.

What are the drivers?