1 / 35

Chromium

Chromium. Mike Houston, Stanford University and The Chromium Community. How Chromium works. Replaces system’s OpenGL driver Industry standard API Support existing unmodified applications Manipulates streams of API commands Alter/inject/discard commands and parameters

rianna
Download Presentation

Chromium

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chromium Mike Houston, Stanford University and The Chromium Community

  2. How Chromium works • Replaces system’s OpenGL driver • Industry standard API • Support existing unmodified applications • Manipulates streams of API commands • Alter/inject/discard commands and parameters • Route commands over a network • Render commands using graphics hardware • State tracking • Allows parallel applications to issue OpenGL • Constrain ordering between multiple streams

  3. Graphics Stream Processing • Treat OpenGL calls as a stream of commands • Form a DAG of stream transformation nodes • Nodes are computers in a cluster • Edges are OpenGL API communication • Each node has a serialization stage and a transformationstage

  4. Stream Serialization S A OpenGL • Convert multiple streams into a single stream • Efficiently context-switch between streams • Constrain ordering using Parallel OpenGL extensions [Igehy98] • Two kinds of serializers: • Network server: • Application: • Unmodified serial application • Custom parallel application

  5. Stream Transformation • Serialized stream is dispatched to “Stream Processing Units” (SPUs) • Each SPU is a shared library • Exports a (partial) OpenGL interface • Each node loads a chain of SPUs at run time • SPUs are generic and interchangeable

  6. SPU Chains • SPUs are loaded as parts of linear chains • Common usage: intercept a few OpenGL calls, pass all others to downstream SPU • Useful for simple state changes, such as “wireframe” drawing

  7. Output Scalability (Sort-First) Server Display Server Display . . . . . . Server Display • Larger displays with unmodifiedapplications • Other possibilities: broadcast, ring network App

  8. Example: Sort-First Server Render Server Render . . . Server Render App Tilesort

  9. Input Scalability (Sort-Last) App App Display . . . App • Parallel geometry extraction • Parallel data submission Server

  10. Example: Sort-Last Application Readback Send Application Readback Send . . . Application Readback Send • Application runs directly on graphics hardware • Same application can use sort-last or sort-first Server Render

  11. SPU Inheritance • The Readback and Render SPUs are related • Readback renders everything except SwapBuffers • Readback inheritsfrom the Render SPU • Override parent’s implementation of SwapBuffers • All OpenGL calls considered “virtual”

  12. Readback’s SwapBuffers void RB_SwapBuffers(void) { self.ReadPixels( 0, 0, w, h, ... ); child.Clear( GL_COLOR_BUFFER_BIT ); child.SemaphorePCR( READBACK_SEMAPHORE ); child.RasterPos2i( tileX, tileY ); child.DrawPixels( w, h, ... ); child.SemaphoreVCR( READBACK_SEMAPHORE ); child.SwapBuffers( ); } • Easily extended to include depth composite • All other functions inherited from Render SPU

  13. More Complicated Example: Hybrid App Server Tilesort Readback Send App Server Tilesort Readback Send . . . . . . App Server Tilesort Readback Send Server Render

  14. Networks Supported • TCP/UDP • Myrinet • Quadrics • Infiniband (coming soon)

  15. New Things to Chromium Dale’s talk • Extensions • DMX Support • Display list management (DLM) • VNC Support • CRUT

  16. Extensions • GL_ARB_fragment_program • GL_ARB_vertex_program • GL_NV_fragment_program • GL_NV_vertex_program • GL_NV_texture_rectangle • GL_EXT_shadow_funcs • GL_EXT_texture_rectangle • GL_IBM_raster_pos_clip

  17. DMX Support • DMX • Distributed Multi-headed X • Single X session across multiple-displays • OpenGL through Chromium • Chromium “DMX aware” • Moving/resizing = retiling • M to N rendering

  18. DMX In Action

  19. Display List Management • Display List Manager (DLM) • State tracking is really tricky • Replay state calls on client • Call list on servers • Bounding Box tracking of display list • Future optimizations • Avoid broadcasting data in display list • Send calls once per server as needed

  20. VNC • X forwarding • Forwards GLX calls to client • DRI bypasses X • Can’t get pixel data • OpenGL apps load Chromium • Render on local host • Readback pixel data • Send to user’s display

  21. What are people doing with Chromium?

  22. Dynamic Screen Calibration

  23. Quake3 Arena Niederauer, et al.

  24. Viewed in a new way Niederauer, et al.

  25. Architectural Analysis • Intercept geometry • Determine floor positions • Change to orthographic view • Insert clip planes at the ceilings • Split floors apart • Multi-pass rendering “Non-Invasive Interactive Visualization of Dynamic Architectural Environments” Christopher Niederauer, Mike Houston, Maneesh Agrawala, Greg HumphreysACM SIGGRAPH 2003 Symposium on Interactive 3D Graphics

  26. Batch Scheduler Integration • Offline rendering to a webpage • Use massive compute resources • Rendering with Vis cluster • Integrate support with RMS Pittsburg Supercomputer Center

  27. Terascale Computing System Compute Nodes Control File Servers /home Interactive Quadrics Switched ethernet Mass Store Viz Archive buffer Summary • 750 Compute Nodes • 3000 EV68 processors • 6 Tf (peak, est >4Tf on LSMS) • 3. TB memory • 27 TB local disk • Multi-rail fat-tree network • Redundant monitor/ctrl • WAN/LAN accessible • Parallel visualization • File servers: 30TB, ~32 GB/s • Mass store, ~1 TB/hr WAN/LAN Pittsburg Supercomputer Center

  28. Example • qsub –l rmsnodes=3:12,other=visnodes=5 • Job waits until 3 nodes (12 cpus) become available AND 5 vis nodes are available • When resources available, job runs • Visit vis web page for rendering Pittsburg Supercomputer Center

  29. What coming in the next year?

  30. General Improvements • Continue to track OpenGL changes • Add extensions • Optimizations • Display list management • Tilesort • Software Compositors

  31. PICA Support • Parallel Image Compositing API (PICA) • API for hardware and software compositing • Will be supported by most hardware compositors • Chromium support • Hooks almost complete • Need software compositors • Readback (N to 1) • Binary-swap • SLIC • Need info from hardware folks

  32. “Vis as a service” • Better integration with schedulers • Reservation systems • Compute/Render/Display • Distributed event model (CRUT) • Compression • Geometry data • Pixel data • Encryption

  33. Look at how much was done last year! • 4 releases • Constant bug fixes • Constant improvements • Constant optimizations Chromium is supported by a large community! Chromium is used in the real world!

  34. Go get it! http://chromium.sourceforge.net

  35. Acknowlegements • The Chromium community • Greg Humphreys • Brian Paul • Joel Welling • Alan Hourihane • DOE!!!

More Related