I have a time-consuming task, so I use parallel to parallelize my script.

my run.sh :

parallel --no-notice 
         --verbose    
         --progress    
          -j 4          
         --ungroup './scripts/chain_base.sh {1} {2} {3}' 
         ::: 150 200 ::: 100 200 500 1000 ::: default v1 < /dev/null

my chain_base.sh like this :

TOKEN_NUM=$1
NUM_ITER=$2
INIT_METHOD=$3

# Reset the SECONDS variable
SECONDS=0
k="5"

for s in $(eval echo "{0..$((k-1))}"); do
python src/abc.py           
   --num_iter ${NUM_ITER}    
   --do_kmeans --k $k         
   --kmeans_split $s           
   --init_method ${INIT_METHOD} 
   --num_tokens ${TOKEN_NUM}     
 done

# Print the end time and execution time
echo "End time: `date`"
echo "Execution time: $SECONDS seconds."

Start using script :

nohup bash scripts/run.sh > run.out &

The current information is.

1. The chain_base.sh can be executed successfully and will not attempt to read any content from the terminal.
2. The Python program takes a long time to execute, approximately 40 minutes.
3. The program always encounters the error message “sh: 1: cannot open /dev/tty: No such device or address“
4. Encountered the following printed logs:

parallel:  SIGHUP received. No new jobs will be started.
parallel:  Waiting for these 4 jobs to finish. Send SIGTERM to stop now.
parallel:  ./scripts/chain_base.sh 150 200 default
parallel:  ./scripts/chain_base.sh 150 500 default
parallel:  ./scripts/chain_base.sh 150 500 v1
parallel:  ./scripts/chain_base.sh 150 200 v1

5. The program can run up to 4 processes in parallel, but some processes may encounter the error “sh: 1: cannot open /dev/tty: No such device or address” and stop, while other processes continue until all 4 processes encounter this error. When the program completely stops, it usually executes 8 tasks, which are the variables {1} in parallel attempting to switch.

6. Add --no-notice to parallel command
   Result: Useless

7. Add < /dev/null to parallel command
   Result: Useless

8. Switch to tmux instead of running as a nohup in the background
   Result: Introduced new problems, mainly Python environment issues. The terminal started by tmux cannot inherit the source terminal environment, and the conda environment is base, causing the run to fail.