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Current State

Nemesis is implemented on Alpha AXP, MIPS and ARM platforms. C libraries have been ported to these platforms to allow programming in a familiar environment; this has required, amongst other things the integration of pervasives rather than statics within the library code. Schedulers as described have been developed; the Jubilee scheduler so far has only been implemented on the ARM platformgif.

A window system which provides primitives similar to X has been implemented. For experimentation this has been implemented both as a traditional shared server to provide server-based rendering and, in the more natural Nemesis fashion, as a library to provide client-based rendering. Experiments have shown that the client based rendering system reduces application crosstalk enormously when best effort applications are competing with continuous media applications rendering video on the display. This work will be reported in detail in the near future.

The ATM device driver for the DEC ATMWorks 750 TURBOchannel takes full advantage of the self-selecting feature of the interface to direct AAL5 adaptation units directly into memory at the position desired by the receiving domain; rendering video from the network requires a single copy from main memory into the frame buffer. (The application must check the frames to discover where they should be placed in the frame buffer.) The combination of the ATMWorks interface and the device driver mean that contention between outgoing ATM streams occurs only as a result of scheduling the processor and when when cells hit the network wire.

I. Leslie, D. McAuley, R. Black, T. Roscoe, P. Barham, D. Evers, R. Fairbairns & E. Hyden