redis中获取没有设置ttl过期时间的key

需求：redis作为一个内存型的数据库，我们需要对过期key保持关注，从info keyspace中可以看出有多少key没有设置过期时间，那么到底是哪些呢？

说明：关于redis ttl 的返回值，请参考http://redisdoc.com/key/ttl.html

测试数据：

5.5.5.101:6379> get c_100
"100"
5.5.5.101:6379> ttl c_100
(integer) -1
5.5.5.101:6379> expire c_100 600
(integer) 1
5.5.5.101:6379> expire c_1000 600
(integer) 1
5.5.5.101:6379> expire c_888 600
(integer) 1
5.5.5.101:6379> dbsize
(integer) 10000
5.5.5.101:6379> info keyspace
# Keyspace
db0:keys=10000,expires=3,avg_ttl=583699

获取没有设置ttl过期的key名字

db_ip=5.5.5.101
db_port=6379
password=abc123
cursor=0
cnt=100
new_cursor=0

redis-cli -h $db_ip -p $db_port -a $password scan $cursor count $cnt > scan_tmp_result
new_cursor=`sed -n '1p' scan_tmp_result`
sed -n '2,$p' scan_tmp_result > scan_result
cat scan_result |while read line
do
    ttl_result=`redis-cli -h $db_ip -p $db_port -a $password ttl $line`
    if [[ $ttl_result == -1 ]];then
        echo $line >> no_ttl.log
    fi
done


while [ $cursor -ne $new_cursor ]
do
    redis-cli -h $db_ip -p $db_port -a $password scan $new_cursor count $cnt > scan_tmp_result
    new_cursor=`sed -n '1p' scan_tmp_result`
    sed -n '2,$p' scan_tmp_result > scan_result
    cat scan_result |while read line
    do
        ttl_result=`redis-cli -h $db_ip -p $db_port -a $password ttl $line`
        if [[ $ttl_result == -1 ]];then
            echo $line >> no_ttl.log
        fi
    done
done
rm -rf scan_tmp_result
rm -rf scan_result

查看结果：

[redis@lxd-vm1 ~]$ wc -l no_ttl.log 
9997 no_ttl.log
[redis@lxd-vm1 ~]$