体心立方铁体系的弹性常数计算，算了五天还没算完，这正常吗？

wfmtg1988

用vasp自带的功能计算体心立方铁体系的弹性常数，计算了五天了，结果还在算，不知道这正不正常啊？本人vasp小白一个，求各位大神指导！！！附上INCAR的参数：
ISTART = 1 # whether or not to read the WAVECAR file.
ICHARG = 1 # how VASP constructs the initial charge density.
LWAVE = .TRUE. # whether the wavefunctions are written to the WAVECAR file
LCHARG = .TRUE. # LCHARG determines whether the charge densities (files CHGCAR and CHG) are written.
LVTOT = .FALSE. # whether the total local potential is written to the LOCPOT file
LVHAR = .FALSE. # whether the electrostatic potential is written to the LOCPOT file
LELF = .FALSE. # whether to create an ELFCAR file or not.

#### Electronic Relaxation ####
ENCUT = 600 # cutoff energy for the planewave basis set in eV
ISMEAR = 1 # how the partial occupancies are set for each orbital.
SIGMA = 0.2 # the width of the smearing in eV.
EDIFF = 1E-7 # global break condition for the electronic SC-loop
NELMIN = 5 # specifies the minimum number of electronic SCF steps.
NELM = 300 # maximum number of electronic SC (selfconsistency) steps
GGA = PE # type of generalized-gradient-approximation one wishes to use.
LREAL = Auto # whether the projection operators are evaluated in real-space or in reciprocal space.
# ALGO = Fast # electronic minimisation algorithm
PREC = Accurate # specifies the "precision"-mode
# ADDGRID = .TRUE. # whether an additional support grid is used for the evaluation of the augmentation charges
ISYM = 0 # determines the way VASP treats symmetry.

#### Magnetic parameters ####
ISPIN = 2
# MAGMOM = 2*3.0
# NUPDOWN = 0
# VOSKOWN = 1

#### Geometry opt parameters ####
EDIFFG = -0.01 # EDIFFG defines the break condition for the ionic relaxation loop.
IBRION = 6 # IBRION determines how the ions are updated and moved.
POTIM = 0.015 # POTIM sets the time step (MD) or step width scaling (ionic relaxations).
NSW = 1 # maximum number of ionic steps.
ISIF = 3 # determines whether the stress tensor is calculated and which principal degrees-of-freedom are allowed to change
NFREE = 4