New and Cool The Cactus Team Albert Einstein Institute

Active Development n Topics: l Remote Visualization l Remote Steering l Remote Offline Visualization l Simulation Portal l Collaboratory Tools l And others... n Groups: l German DFN-Verein Gigabit project for exploiting high speed networks (TIKSL) l USA NSF KDI project to develop collaboratory tools for astrophysics around Cactus (ASC) l And others...

Remote Visualization IsoSurfaces and Geodesics Contour plots (download) Grid Functions Streaming HDF5 Amira LCA Vision OpenDX

Remote Visualization n Streaming data from Cactus simulation to viz client l Clients: OpenDX, Amira, LCA Vision,... n Protocols l Proprietary: –Isosurfaces, geodesics l HTTP: –Parameters, xgraph data, JPegs l Streaming HDF5: –HDF5 provides downsampling and hyperslabbing –all above data, and all possible HDF5 data (e.g. 2D/3D) –two different technologies Streaming Virtual File Driver (I/O rerouted over network stream) XML-wrapper (HDF5 calls wrapped and translated into XML)

Remote Visualization (2) n Clients l Proprietary: –Amira l HTTP: –Any browser (+ xgraph helper application) l HDF5: –Any HDF5 aware application h5dump Amira OpenDX LCA Vision (soon) l XML: –Any XML aware application Perl/Tk GUI Future browsers (need XSL-Stylesheets)

OpenDX n Open source, (free), multiplatform, large active development community, easy to program n Reads HDF5 (Cactus) data from file or remotely streamed from Cactus n Simple GUI, select different hyperslabs from 3D data n Also support for streamed ASCII data from Cactus

LCA Vision n Freely available, developed at NCSA n Simple to use n Reads Cactus data created from FlexIO interfaces n Work on integrating HDF5 (e.g. streaming capabilities)

Remote Visualization - Issues n Parallel streaming l Cactus can do this, but readers not yet available on the client side n Handling of port numbers l clients currently have no method for finding the port number that Cactus is using for streaming l development of external meta-data server needed (ASC/TIKSL) n Generic protocols n Data server l Cactus should pass data to a separate server that will handle multiple clients without interfering with simulation l TIKSL provides middleware (streaming HDF5) to implement this n Output parameters for each client

Remote Steering Remote Viz data XML HTTP HDF5 Amira Any Viz Client

Remote Steering n Stream parameters from Cactus simulation to remote client, which changes parameters (GUI, command line, viz tool), and streams them back to Cactus where they change the state of the simulation. n Cactus has a special STEERABLE tag for parameters, indicating it makes sense to change them during a simulation, and there is support for them to be changed. n Example: IO parameters, frequency, fields n Current protocols: l XML (HDF5)to standalone GUI l HDF5to viz tools (Amira) l HTTPto Web browser (HTML forms)

Thorn http n Thorn which allows simulation to act as a web server n Connect to simulation from any browser n Monitor run: parameters, basic visualization,... n Change steerable parameters n See running example at n Wireless remote viz, monitoring and steering

Remote Steering - Issues n Same kinds of problems as remote visualization l generic protocols l handling of port numbers l broadcasting of active Cactus simulations n Security l Logins l Who can change parameters? n Lots of issues still to resolve...

Remote Offline Visualization Viz Client (Amira) HDF5 VFD DataGrid (Globus) DPSS FTP HTTP Visualization Client DPSS Server FTP Server Web Server Remote Data Server Downsampling, hyperslabs Viz in Berlin 4TB at NCSA Only what is needed

Remote Offline Visualization n Accessing remote data for local visualization n Should allow downsampling, hyperslabbing, etc. n Access via DPSS is working (TIKSL) n Waiting for DataGrid support for HTTP and FTP to remove dependency on the DPSS file systems.

Grand Picture Remote steering and monitoring from airport Origin: NCSA Remote Viz in St Louis T3E: Garching Simulations launched from Cactus Portal Grid enabled Cactus runs on distributed machines Remote Viz and steering from Berlin Viz of data from previous simulations in SF café DataGrid/DPSS Downsampling Globus http HDF5 IsoSurfaces

More Information n Web pages: l Cactus: – l DFN: – l ASC: – n Contact: l