  We report our measurements for orbital and spin parameters of X 1822-371
using its X-ray partial eclipsing profile and pulsar timing from data collected
by the Rossi X-ray Timing Explorer (RXTE). Four more X-ray eclipse times
obtained by the RXTE 2011 observations were combined with historical records to
trace evolution of orbital period. We found that a cubic ephemeris likely
better describes evolution of the X-ray eclipse times during a time span of
about 34 years with a marginal second order derivative of
$\ddot{P}_{orb}=(-1.05 \pm 0.59) \times 10^{-19}$ s$^{-1}$. Using the pulse
arrival time delay technique, the orbital and spin parameters were obtained
from RXTE observations from 1998 to 2011. The detected pulse periods show that
the neutron star in X 1822-371 is continuously spun-up with a rate of
$\dot{P}_{s}=(-2.6288 \pm 0.0095) \times 10^{-12}$ s s$^{-1}$. Evolution of the
epoch of the mean longitude $l=\pi /2$ (i.e. $T_{\pi / 2}$) gives an orbital
period derivative value consistent with that obtained from the quadratic
ephemeris evaluated by the X-ray eclipse but the detected $T_{\pi / 2}$ values
are significantly and systematically earlier than the corresponding expected
X-ray eclipse times by $90 \pm 11$ s. This deviation is probably caused by
asymmetric X-ray emissions. We also attempted to constrain the mass and radius
of the neutron star using the spin period change rate and concluded that the
intrinsic luminosity of X 1822-371 is likely more than $10^{38}$ ergs s$^{-1}$.
