#!/usr/sbin/dtrace -s

dtrace:::BEGIN
{
	vtotal = 0;
}

syscall::$1:entry
/pid == $target/
{
	self->vtime = vtimestamp;
}

syscall:::return
/self->vtime/
{
	@vtime[ustack()] = sum(vtimestamp - self->vtime);
	vtotal += (vtimestamp - self->vtime);
	self->vtime = 0;
}

dtrace:::END
{
	normalize(@vtime, vtotal / 100);
        printa(@vtime);
}