Memcached安装过程

http://memcached.org/ 下载解压进入目录，阅读README
Dependencies:

   -- libevent, http://www.monkey.org/~provos/libevent/ (libevent-dev)

If using Linux, you need a kernel with epoll.  Sure, libevent will
work with normal select, but it sucks.

epoll isn't in Linux 2.4, but there's a backport at:

    http://www.xmailserver.org/linux-patches/nio-improve.html

You want the epoll-lt patch (level-triggered).

去下载libevent后，解压并进入目录，阅读README,
执行
$ ./configure
$ make
$ make verify   # (optional)
$ sudo make install
果然在$ make verify   # (optional)这一步报错：
EPOLL
test-eof: OKAY
test-weof: OKAY
test-time: OKAY
test-changelist: OKAY
regress: [Error code 3]
  FAIL regress_dns.c:188: assert(dns_ok == DNS_PTR): 0 vs 2dns/gethostbyaddr:
  FAIL regress_main.c:303: Legacy unit test failed
  [gethostbyaddr FAILED]
1/177 TESTS FAILED. (0 skipped)
FAILED
就是Memcached文档中提到的epoll isn't in Linux 2.4。这个错误我暂时不去解决。
然后进入memcached目录，执行
$./configure
$sudo make install

现在我要启动memcached。

root@loveztt:/usr/local/bin# ./memcached restart
./memcached: error while loading shared libraries: libevent-2.0.so.5: cannot open shared object file: No such file or directory
root@loveztt:/usr/local/bin# LD_DEBUG=libs /usr/local/bin/memcached -v
     ......
     15730:   trying file=/usr/lib/libevent-2.0.so.5
     15730:
/usr/local/bin/memcached: error while loading shared libraries: libevent-2.0.so.5: cannot open shared object file: No such file or directory
root@loveztt:/usr/local/bin# ln -s /home/zj/Downloads/ProgrammerSoft/libevent-2.0.16-stable/.libs/libevent-2.0.so.5 /usr/lib/libevent-2.0.so.5
root@loveztt:/usr/local/bin# ./memcached restart
can't run as root without the -u switch
$su zj
$memcached
failed to listen on TCP port 11211: Address already in use
zj@loveztt:~$ netstat -ap | grep 11211
(Not all processes could be identified, non-owned process info
will not be shown, you would have to be root to see it all.)
^C
zj@loveztt:~$ su
Password:
root@loveztt:/home/zj# netstat -ap | grep 11211
tcp        0      0 *:11211                 *:*                     LISTEN      16110/memcached
tcp6       0      0 [::]:11211              [::]:*                  LISTEN      16110/memcached
udp        0      0 *:11211                 *:*                                 16110/memcached
udp6       0      0 [::]:11211              [::]:*                              16110/memcached