diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 02e3b01..b014837 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -24,6 +24,9 @@ jobs:
     steps:
     - uses: actions/checkout@v4
 
+    - name: Install coreutils
+      run: brew install coreutils
+
     - name: Run testing script on macOS
       run: ./testing.sh
 
diff --git a/.gitignore b/.gitignore
index a00bc94..629c291 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
 test.log
 error.log
 rebalance_db.txt
-testing_data
\ No newline at end of file
+testing_data
+.vscode
\ No newline at end of file
diff --git a/testing.sh b/testing.sh
index 4fe7333..f531e1e 100755
--- a/testing.sh
+++ b/testing.sh
@@ -9,6 +9,7 @@ log_std_file=./test.log
 log_error_file=./error.log
 test_data_src=./test/pool
 test_pool_data_path=./testing_data
+test_pool_data_size_path=$test_pool_data_path/size
 
 ## Color Constants
 
@@ -18,6 +19,7 @@ Color_Off='\033[0m' # Text Reset
 # Regular Colors
 Red='\033[0;31m'    # Red
 Green='\033[0;32m'  # Green
+Yellow='\033[0;33m' # Yellow
 Cyan='\033[0;36m'   # Cyan
 
 ## Functions
@@ -40,6 +42,21 @@ function prepare() {
   cp -rf $test_data_src $test_pool_data_path
 }
 
+# return time to the milisecond
+function get_time() {
+
+  case "$OSTYPE" in
+    darwin*)
+      date=$(gdate +%s%N)
+      ;;
+    *)
+      date=$(date +%s%N)
+      ;;
+  esac
+
+  echo "$date"
+}
+
 function assertions() {
   # check error log is empty
   if grep -q '[^[:space:]]' $log_error_file; then
@@ -63,6 +80,14 @@ function assert_matching_file_not_copied() {
   fi
 }
 
+function print_time_taken(){
+  time_taken=$1
+  minute=$((time_taken / 60000))
+  seconde=$((time_taken % 60000 / 1000))
+  miliseconde=$((time_taken % 1000))
+  color_echo "$Yellow" "Time taken: ${minute}m ${seconde}s ${miliseconde}ms"
+}
+
 color_echo "$Cyan" "Running tests..."
 
 color_echo "$Cyan" "Running tests with default options..."
@@ -108,4 +133,61 @@ assert_matching_file_not_copied "mp4.txt"
 assertions
 color_echo "$Green" "Tests passed!"
 
-color_echo "$Green" "All tests passed!"
\ No newline at end of file
+color_echo "$Cyan" "Running tests with different file count and size..."
+prepare
+
+mkdir -p $test_pool_data_size_path
+
+color_echo "$Cyan" "Creating 1000 files of 1KB each..."
+mkdir -p $test_pool_data_size_path/small
+for i in {1..1000}; do
+  dd if=/dev/urandom of=$test_pool_data_size_path/small/file_"$i".txt bs=1024 count=1 >> /dev/null 2>&1
+done
+
+color_echo "$Cyan" "Creating 5 file of 1GB each..."
+mkdir -p $test_pool_data_size_path/big
+for i in {1..5}; do
+  dd if=/dev/urandom of=$test_pool_data_size_path/big/file_"$i".txt bs=1024 count=1048576 >> /dev/null 2>&1
+done
+
+color_echo "$Green" "Files created!"
+
+echo "Running rebalancing on small files..."
+# measure time taken
+start_time=$(get_time)
+./zfs-inplace-rebalancing.sh $test_pool_data_size_path/small >> $log_std_file 2>> $log_error_file
+end_time=$(get_time)
+time_taken=$(( (end_time - start_time) / 1000000 ))
+print_time_taken $time_taken
+assertions
+color_echo "$Green" "Tests passed!"
+
+echo "Running rebalancing on big files..."
+rm -f rebalance_db.txt
+# measure time taken
+start_time=$(get_time)
+./zfs-inplace-rebalancing.sh $test_pool_data_size_path/big >> $log_std_file 2>> $log_error_file
+end_time=$(get_time)
+time_taken=$(( (end_time - start_time) / 1000000 ))
+print_time_taken $time_taken
+assertions
+color_echo "$Green" "Tests passed!"
+
+echo "Running rebalancing on all files..."
+rm -f rebalance_db.txt
+# measure time taken
+start_time=$(get_time)
+./zfs-inplace-rebalancing.sh $test_pool_data_size_path >> $log_std_file 2>> $log_error_file
+end_time=$(get_time)
+time_taken=$(( (end_time - start_time) / 1000000 ))
+print_time_taken $time_taken
+assertions
+color_echo "$Green" "Tests passed!"
+
+color_echo "$Green" "All tests passed!"
+color_echo "$Cyan" "Cleaning"
+rm -f $log_std_file
+rm -f $log_error_file
+rm -f rebalance_db.txt
+rm -rf $test_pool_data_path
+