Minimizing Scheduling Delay for Multimedia in Xen Hypervisor

A State-of-the-Art Survey on Real-Time Issues in Embedded Systems Virtualization

“…Lee et al [46] improved performance of multimedia applications in Xen by assigning higher fixed-priorities to Domain0 and other real-time domains than non-realtime domains, which are scheduled by the default credit scheduler.…”

“…Introduction of these hypercalls implies that the resulting system is no longer a strict fullvirtualization system as the conventional KVM. Zhang et al [47] presented two real-time improvements to KVM with coexisting RTOS and GPOS guests: giving the guest RTOS vCPUs higher priority than GPOS vCPUs; use CPU shielding to dedicate one CPU core to the RTOS guest and shield it from GPOS interrupts, by setting the CPU affinity parameter of both host OS processes and interrupts. Experimental results indicate that the RTOS interrupt response latencies are reduced.…”

“…Experimental results indicate that the RTOS interrupt response latencies are reduced. Based on the work of [47], Zuo et al [48] presented additional improvements by adding two hypercalls that enable the guest OS to boost priority of its vCPU when a highpriority task is started, e.g., like an interrupt handler, and deboost it when the high-priority task is finished.…”

“…The company SysGo AG developed PikeOS, which evolved from a L4-microkernel, designed for safetycritical applications. Kaiser et al [62] described the scheduling algorithm in PikeOS, which is a combination of priority-based, time-driven and proportional share scheduling. Each real-time VM is assigned a fixed-priority decided by the designer, hence a time-driven VM can have lower or higher priority values than an event-driven VM.…”

“…Non real-time VMs execute in the background when real-time VMs are not active. Yang et al [63] developed a two-level Compositional Scheduling Architecture (CSA), using the L4/Fiasco microkernel as a VMM and L4Linux as a VM.…”