rem: thread_set_priority(tid, THREAD_LOWEST_PRIORITY);
add: thread_set_priority(tid, B_LOWEST_ACTIVE_PRIORITY);
context: int vm_page_init_postthread(kernel_args *ka){	thread_id tid;	// create a kernel thread to clear out pages	tid = thread_create_kernel_thread("page scrubber", &page_scrubber, NULL);	thread_set_priority(tid, THREAD_LOWEST_PRIORITY);	thread_resume_thread(tid);	modified_pages_available = create_sem(0, "modified_pages_avail_sem");#if 0	// create a kernel thread to schedule modified pages to write	tid = thread_create_kernel_thread("pageout daemon", &pageout_daemon, THREAD_MIN_RT_PRIORITY + 1);	thread_resume_thread(tid);#endif	return 0;}