Bump KVMFR to version 28 and attach generation, epoch, and deadline
identities to cadence deliveries and their timing records.
Accept phase corrections only for the exact completed publication. Keep
VM and client clocks independent by exchanging relative phase errors.
Make submission, completion, and work-estimate accounting best effort
so scheduler state cannot delay GPU submission or frame publication.
Advance past cadence deadlines whose publication targets have already
expired after a completed periodic frame.
Use the same slack, work, and safety lead as target selection so the next
publisher wait cannot immediately expire again.
Replace the shared force and republish booleans with request tickets.
A completed publication now acknowledges only requests captured when it
began, so a concurrent immediate or cadence-break request survives.
Treat a forced publication as periodic once the normal pre-deadline
send point is due. This prevents an immediate forced copy from being
followed by another copy for the same cadence slot.
Keep the client schedule floor at 2 ms while accepting shorter guest
frame intervals for cadence tracking. This lets sources above 500 Hz
trigger immediate final-frame delivery when their cadence breaks.
Derive the source rate from unique frames observed over the actual log
interval. The old EWMA discarded intervals below 2 ms, capping the
reported rate at 500 Hz and understating high-rate sources.
Prepare each acquired content frame into one of two private GPU
candidates so the IddCx frame can be released without copying it to
IVSHMEM immediately.
Wake a high-resolution publisher at the client deadline and send the
newest completed candidate. Preserve accumulated damage across
superseded candidates, include the scheduling hold in end-to-end timing,
and keep transport work on the existing physical copy queue.
Discard the learned guest arrival period when a frame follows a gap
much larger than expected. Force that frame through and relearn the
arrival rate so sparse updates are not held for a frame that never
arrives.
