#!/sbin/openrc-run

description="VRAM Swap via NBD (CUDA memcpy backend)"
command="/usr/bin/nbd-vram"
command_background="yes"
pidfile="/run/nbd-vram-swap.pid"
output_log="/var/log/nbd-vram-swap.log"
error_log="/var/log/nbd-vram-swap.log"

# Defaults — overridden by /etc/conf.d/nbd-vram-swap (sourced by OpenRC before this file)
: ${VRAM_SETUP_SIZE_MB:=7168}
: ${VRAM_SWAP_PRIORITY:=1500}
: ${VRAM_NBD_THREADS:=4}
: ${VRAM_NBD_CONNECTIONS:=4}
# Export at top level so nbd-vram-connect.sh (called from start_post) inherits them
export VRAM_SETUP_SIZE_MB VRAM_SWAP_PRIORITY VRAM_NBD_THREADS VRAM_NBD_CONNECTIONS

depend() {
	# Start after the display manager so the GPU is initialized for CUDA
	# (PRIME offload needs X to claim the GPU first on hybrid laptops)
	after modules xdm
	use logger
}

start_pre() {
	nvidia-smi -pm 1 || true
	sysctl -w vm.swappiness=200 vm.min_free_kbytes=524288
}

start_post() {
	local timeout=60
	while [ "${timeout}" -gt 0 ]; do
		[ -S /run/nbd-vram.sock ] && break
		sleep 1
		: $(( timeout -= 1 ))
	done
	[ -S /run/nbd-vram.sock ] || { eerror "nbd-vram socket not ready after 60s"; return 1; }
	/usr/bin/nbd-vram-connect.sh || return 1
	[ -r "${pidfile}" ] && \
		echo -1000 > "/proc/$(cat "${pidfile}")/oom_score_adj" 2>/dev/null || true
}

stop_pre() {
	/usr/bin/nbd-vram-disconnect.sh || return 1
}

stop() {
	ebegin "Stopping ${RC_SVCNAME}"
	start-stop-daemon --stop --quiet --pidfile "${pidfile}" \
		--retry TERM/1800 --oknodo
	eend $?
}