Question about fix command syntax when restart simulation

Dear LAMMPS users,

I performed a simulation about cooling process of B2 NiAl alloy using npt ensemble. Because the cooling process is too long (from 2500 K to 0.01 K in 6000000 steps), I used the restart command to save the data to continue on the next day( the simulation stopped at time step = 4600000 at temperature 668.20264 K, restart.4600000). But after using read_restart command to continue the simulation, the fix npt has started from the Tstart=2500 K instead of continue the previous run with Tstart=668.20264 K). My question is: Do we have to modify the Tstart value in fix npt to continue the previous simulation by using read_restart command? Thank you for your time and help!

These are the original script, and modified script for second run. The simulations were performed using LAMMPS with GPU package on Ubuntu 16.04 x64 with 2 Intel Xeon and 2 NVIDIA Tesla C2050. The scripts were run by following command:

mpirun -np 16 lmp_mpi -sf gpu -pk gpu 2 -in in.script

#----------------------- ORIGINAL SCRIPT------------------------------

------------------------ INITIALIZATION ----------------------------

units metal
dimension 3
boundary p p p
atom_style atomic

----------------------- ATOM DEFINITION ----------------------------

lattice custom 2.88 a1 1.0 0.0 0.0 a2 0.0 1.0 0.0 a3 0.0 0.0 1.0&
basis 0.0 0.0 0.0 basis 0.5 0.5 0.5

region box block -10.0 10.0 -10.0 10.0 -10.0 10.0
create_box 2 box

create_atoms 2 box basis 1 1 basis 2 2

group Ni type 1
group Al type 2

mass 1 58.7
mass 2 27.0

------------------------ FORCE FIELDS ------------------------------

pair_style eam/alloy
pair_coeff * * Mishin-Ni-Al-2009.eam.alloy Ni Al

velocity all create 2500 4922459 dist gaussian

thermo 10000
thermo_style custom step lx ly lz temp etotal pe press vol pxx pyy pzz pyz pxz pxy

#Equilibration for 2 ns
fix 1 all npt temp 2500 2500 0.5 iso 0 0 1.0
dump 1 all custom 1000 dump.equil.* id type mass xs ys zs vx vy vz fx fy fz

restart 100000 equil.*

run 2000000

unfix 1
undump 1

#Cooling and collecting data for analysis

reset_timestep 0

variable Temperature equal temp
variable TEnergy equal etotal
variable KEnergy equal ke
variable PEnergy equal pe
variable Pr equal press
variable Volu equal vol

fix 2 all npt temp 2500 0.01 0.1 iso 0 0 0.2

fix 3 all ave/time 1000 10 10000 v_Temperature v_TEnergy v_KEnergy v_PEnergy v_Pr v_Volu file data.out

dump 2 all custom 1000 dump.cooling.* id type mass xs ys zs vx vy vz fx fy fz

restart 100000 cooling.*

run 6000000

Dear LAMMPS users,

I performed a simulation about cooling process of B2 NiAl alloy using npt
ensemble. Because the cooling process is too long (from 2500 K to 0.01 K in
6000000 steps), I used the restart command to save the data to continue on
the next day( the simulation stopped at time step = 4600000 at temperature
668.20264 K, restart.4600000). But after using read_restart command to
continue the simulation, the fix npt has started from the Tstart=2500 K
instead of continue the previous run with Tstart=668.20264 K). My question
is: Do we have to modify the Tstart value in fix npt to continue the
previous simulation by using read_restart command? Thank you for your time
and help!

​no, but you have to make an adjustment to the "run" command. please see
the "start" "stop" options:
​http://lammps.sandia.gov/doc/run.html

axel.