Real-Time X-Server Graphics Under KURT-Linux Group Scheduling Control

1. Real-Time X-Server Graphics Under KURT-Linux Group Scheduling Control Client Client Scheduler Display Client Implementation GS Client State Variables Client Scheduler Display Client X.org X-Server Goals and Objectives • Abstracts access to graphic display • Server through which all graphics events pass. • Clients can be local or remote • Uses a simple round-robin scheduler to control client event processing • Problem: Real-time computations which calculate graphics for display have no control over when the display occurs • Solution: Use KURT-Linux Group Scheduling to represent both calculation and display as a single computation under unified control. • Transfer X-Server scheduling decisions into the Group Scheduling domain to unify control of the computation • Group Scheduling will control calculation by the client and processing of generated events by X-Server as required by scheduling policy for the graphic display computation X Server Driving Example Experiments • X Server state variables, in a memory segment shared with Group Scheduler, control client's event stream processing • Each graphic display computation will be represented by a group containing the calculation and X-server threads • Group Scheduler ensures timely completion of the computation as a whole: calculation and display threads • Multiple display computations on a single KURT-Linux machine with different scheduling constraints • Display calculated by each should satisfy constraints • N computations on N clock-synchronized machines with each machine displaying the state of all computations. • Real-time control under Group Scheduling will allow us to ensure that all displays on all machines are synchronized • Results: Operational demonstration that computations composed from groups of functional units can be directly controlled under Group Scheduling X 040205