Bash script for testing USB disk read and write speed for macOS

check_disk_speed.sh

#!/bin/bash
# Disk info + speed test for mounted volume

# --- PARAMETERS ---
FILE="tstfile"
COUNT=1024
BS=1024k
# ------------------

VOLUME_PATH="$PWD"
VOLUME_NAME=$(echo "$VOLUME_PATH" | sed -E 's|^/Volumes/([^/]+)(/.*)?$|\1|')

echo "$VOLUME_NAME"

disk_info=$(system_profiler SPUSBDataType 2>/dev/null)
disk_block=$(echo "$disk_info" | grep -E "^\s*$VOLUME_NAME:$" -B20 -A8)

capacity=$(echo "$disk_block" | awk '/Capacity:/ {print $2 " " $3; exit}')
free_space=$(echo "$disk_block" | awk '/Free:/ {print $2 " " $3; exit}')
filesystem=$(echo "$disk_block" | awk '/File System:/ {print $3; exit}')
bsd_name=$(echo "$disk_block" | awk '/BSD Name:/ {print $3; exit}')
mount_point=$(echo "$disk_block" | sed -n 's/^.*Mount Point:[[:space:]]*//p')
usb_speed=$(echo "$disk_block" | sed -n 's/^.*Speed:[[:space:]]*//p')

echo "Mount Point: $mount_point"
echo "    Capacity: $capacity"
echo "    Free: $free_space"
echo "    File System: $filesystem"
echo "    BSD Name: $bsd_name"
echo "    Bus Speed: $usb_speed"

TMP_FILE="$VOLUME_PATH/$FILE"

spinner() {
    local pid=$1
    local message="${2}"
    local delay=0.1
    local spin='-\|/-'
    local i=0
    while kill -0 "$pid" 2>/dev/null; do
        i=$(( (i + 1) % 4 ))
        printf "\r[ %c ] ${message}..." "${spin:i:1}" >/dev/tty
        sleep "$delay"
    done
}

spinwait() {
    local pid=$1
    local message="${2:-Task}"
    spinner $pid "$message" &
    local spid=$!
    wait $pid
    kill $spid 2>/dev/null
    printf "\r[ %s ] %s - Done\n" "*" "$message" >/dev/tty
}

write_speed_bytes=$(
    {
        echo "$( { dd if=/dev/zero of="$TMP_FILE" oflag=sync bs=$BS count=$COUNT; } 2>&1 | awk -F'[()]' '/bytes\/sec/ {gsub(/ bytes\/sec/,"",$2); print $2; exit}' )"
    } &
    spinwait $! "Testing write 1GB"
)
[ -z "$write_speed_bytes" ] && write_speed_bytes=0
write_speed=$(awk -v b="$write_speed_bytes" 'BEGIN {printf "%.1f", b/1024/1024}')
echo "Write Speed: $write_speed MB/s"



read_speed_bytes=$(
    {
        echo "$( { dd if="$TMP_FILE" of=/dev/null bs=$BS count=$COUNT; } 2>&1 | awk -F'[()]' '/bytes\/sec/ {gsub(/ bytes\/sec/,"",$2); print $2; exit}' )"
    } &
    spinwait $! "Testing read 1GB"
)

[ -z "$read_speed_bytes" ] && read_speed_bytes=0
read_speed=$(awk -v b="$read_speed_bytes" 'BEGIN {printf "%.1f", b/1024/1024}')
echo "Read Speed: $read_speed MB/s"

rm -f "$TMP_FILE"

Navigate to your disk

cd /Volume/...

Execute:

bash -c "$(curl -fsSL https://gist.githubusercontent.com/andriitishchenko/00b9a32a6e64b35e8b0ff388d8c78fff/raw/148f185954bdac513b329a0f428acabef5140258/check_disk_speed.sh)"

Expected output

Mount Point: /Volumes/Untitled
Capacity: 62,91 GB
Free: 62,9 GB
File System: ExFAT
BSD Name: disk2
Bus Speed: Up to 480 Mb/s
[ * ] Testing write 1GB - Done
Write Speed: 16.2 MB/s
[ * ] Testing read 1GB - Done
Read Speed: 33.5 MB/s