How can I monitor the TBW on my Samsung SSD?

FULL DISCLOSURE: The scipt/commands present in this answer are not my own, but rather the work of J. D. G. Leaver. They were sourced from a blog post on his website.

NB:

• This will only report accurate numbers for Samsung SSDs.
• You need to have smartctl installed, from the package smartmontools.

Method 1:

Here's a handy little script that will allow you to monitor the TBW of your SSD, along with some other information:

#!/bin/bash

#######################################
# Variables                           #
#######################################

SSD_DEVICE="/dev/sda"

ON_TIME_TAG="Power_On_Hours"
WEAR_COUNT_TAG="Wear_Leveling_Count"
LBAS_WRITTEN_TAG="Total_LBAs_Written"
LBA_SIZE=512 # Value in bytes

BYTES_PER_MB=1048576
BYTES_PER_GB=1073741824
BYTES_PER_TB=1099511627776

#######################################
# Get total data written...           #
#######################################

# Get SMART attributes
SMART_INFO=$(sudo /usr/sbin/smartctl -A "$SSD_DEVICE")

# Extract required attributes
ON_TIME=$(echo "$SMART_INFO" | grep "$ON_TIME_TAG" | awk '{print $10}')
WEAR_COUNT=$(echo "$SMART_INFO" | grep "$WEAR_COUNT_TAG" | awk '{print $4}' | sed 's/^0*//')
LBAS_WRITTEN=$(echo "$SMART_INFO" | grep "$LBAS_WRITTEN_TAG" | awk '{print $10}')

# Convert LBAs -> bytes
BYTES_WRITTEN=$(echo "$LBAS_WRITTEN * $LBA_SIZE" | bc)
MB_WRITTEN=$(echo "scale=3; $BYTES_WRITTEN / $BYTES_PER_MB" | bc)
GB_WRITTEN=$(echo "scale=3; $BYTES_WRITTEN / $BYTES_PER_GB" | bc)
TB_WRITTEN=$(echo "scale=3; $BYTES_WRITTEN / $BYTES_PER_TB" | bc)

# Output results...
echo "------------------------------"
echo " SSD Status:   $SSD_DEVICE"
echo "------------------------------"
echo " On time:      $(echo $ON_TIME | sed ':a;s/\B[0-9]\{3\}\>/,&/;ta') hr"
echo "------------------------------"
echo " Data written:"
echo "           MB: $(echo $MB_WRITTEN | sed ':a;s/\B[0-9]\{3\}\>/,&/;ta')"
echo "           GB: $(echo $GB_WRITTEN | sed ':a;s/\B[0-9]\{3\}\>/,&/;ta')"
echo "           TB: $(echo $TB_WRITTEN | sed ':a;s/\B[0-9]\{3\}\>/,&/;ta')"
echo "------------------------------"
echo " Mean write rate:"
echo "        MB/hr: $(echo "scale=3; $MB_WRITTEN / $ON_TIME" | bc | sed ':a;s/\B[0-9]\{3\}\>/,&/;ta')"
echo "------------------------------"
echo " Drive health: ${WEAR_COUNT} %"
echo "------------------------------"

Here's a sample of the output:

------------------------------
 SSD Status:   /dev/sda
------------------------------
 On time:      2 hr
------------------------------
 Data written:
           MB: 25,098.917
           GB: 24.510
           TB: .023
------------------------------
 Mean write rate:
        MB/hr: 12,549.458
------------------------------
 Drive health: 100 %
------------------------------

This data is accurate, as I only just installed my new 850 Pro.

Method 2:

Alternatively, here's a one-liner to get the TBW only:

echo "GB Written: $(echo "scale=3; $(sudo /usr/sbin/smartctl -A /dev/sda | grep "Total_LBAs_Written" | awk '{print $10}') * 512 / 1073741824" | bc | sed ':a;s/\B[0-9]\{3\}\>/,&/;ta')"

Crucial SSD Lifetime remaining

For Crucial SSD percentage lifetime remaining see

https://www.crucial.com/support/articles-faq-ssd/ssds-and-smart-data

This doc identifies 202 as Percent Lifetime Remaining. As an example on Ubuntu 16.04 (sudo smartctl /dev/sda1 -a)(part of smartmontools) reports 202 as unknown, but the value of 90 indicates 90% life remaining. On Ubuntu 20.04, the Lifetime Remaining is recognized and listed correctly