Bash script that prints out the largest key in your Redis store.

redis_max_key_size.sh

#!/usr/bin/env bash

# This script prints out the largest key in your Redis store. 
# This script was forked from Brent O'Connor at https://gist.github.com/epicserve/5699837. It was subsequently modified by Aaron Alfson.
# License: http://www.apache.org/licenses/LICENSE-2.0

human_size() {
        awk -v sum="$1" ' BEGIN {hum[1024^3]="Gb"; hum[1024^2]="Mb"; hum[1024]="Kb"; for (x=1024^3; x>=1024; x/=1024) { if (sum>=x) { printf "%.2f %s\n",sum/x,hum[x]; break; } } if (sum<1024) print "1kb"; } '
}

redis_cmd='redis-cli'

max_key='';
max_key_size=0;

# get keys and sizes
for k in `$redis_cmd keys "*"`; do 
	key_size_bytes=`$redis_cmd debug object $k | perl -wpe 's/^.+serializedlength:([\d]+).+$/$1/g'`; 
	
	# check to see if current key size is greater than the current max key size. 
	if [ $key_size_bytes -gt $max_key_size ]
	then
		max_key=$k; 
		max_key_size=$key_size_bytes; 
		
		size=`echo $l | perl -wpe 's/^(\d+).+/$1/g'`; 
		hsize=`human_size "$size"`
		
		key_type=`$redis_cmd TYPE $max_key`;

		echo "Current max_key: $max_key, max_key_size: $hsize, TYPE: $key_type"
	fi
done

# print out current key size in human readable form. 
size=`echo $l | perl -wpe 's/^(\d+).+/$1/g'`; 
hsize=`human_size "$size"`
key_type=`$redis_cmd TYPE $max_key`;

echo "Final max_key: $max_key, max_key_size: $hsize, TYPE: $key_type"