NSEC2SEC
elapsed = NSEC2SEC((double)(gethrtime() - start));
elapsed = NSEC2SEC((double)(gethrtime() - start));
NSEC2SEC(sync_time_ns) >= zfs_txg_timeout)) ||
NSEC2SEC(sync_time_ns) >= zfs_txg_timeout)) ||
NSEC2SEC(import_expire - gethrtime()));
NSEC2SEC(gethrtime() - spa->spa_spares_last_polled) >