/output/custom/31/7/31767937
/output/custom/31/7/317537a
/output/custom/31/7/317537
/output/custom/31/7/317ab
/output/custom/31/7/317bo
/output/custom/31/7/317je
/output/custom/31/7/317ma
/output/custom/31/7/31763

for i in $(ls x*)
do
    tar -cf /tar/$i.tar -T $i &
done