#!/bin/bash
dir_num=0
max_threshold=100000

while [ $dir_num -lt $max_threshold ] ; do
let dir_num=dir_num+1
cd /home1
mkdir  a.$dir_num

        num=0
        while [ $num -lt $max_threshold ] ; do
        let num=num+1
        cd /home1/a.$dir_num
        dd if=/dev/zero of=a.$num bs=1 count=$num
        done
done