memcached一般是很多服务器一起做缓存的，而且每个数据都是通过客户端散列到各个服务器。如果想通过telnet删除一个key可就麻烦了，你可能需要一个一个的找，2-3个服务器还行，如果是几十个的时候就麻烦了。

在这里给出一个脚本来执行这样的任务。

#!/bin/sh
# description delete entries by batch mode.
# useage ./clear.sh key1 key2 key3 ...
KEYS=$@
HOSTS=("127.0.0.1" "127.0.0.1" "127.0.0.01" "127.0.0.1")
PORTS=(10000 10001 10002 10003)
if [ $# = 0 ];then
echo "key set is empty!"
exit 0
fi
HOSTS_LEN=${#HOSTS[@]}
for ((p=0;p<$#;p++)); do
for ((i=0;i<HOSTS_LEN;i++)); do
(
#sleep 1
#echo "delete ${KEYS[$p]}"
echo "stats"
sleep 1
echo "quit"
)|telnet ${HOSTS[$i]} ${PORTS[$i]}
echo
done
done
echo "delete key sets [$@] finished!"

 memcache batch delete

memcached batch delete