在小网站上MySQL高CPU使用率

我有一个专门的服务器上的小型网站（FreeBSD 9.2，MySQL 5.6.1和PHP 5.5.5）。 问题是，即使网站有一些访问者，MySQL也会消耗大量的cpu资源。 数据库很小（最大的表约为12k行）

我已经启用慢查询loginmy.conf，但没有logging查询。

错误日志文件不包含任何有用的信息（实际上它是空的）

这里是服务器规格

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• 我的磁盘失败，并在Linux上造成高负载？
• SQL Azure插入查询比V11慢十倍？
• 持续的顺序写入导致性能严重下降

中央处理器

hw.machine: amd64 hw.model: Intel(R) Xeon(R) CPU X3330 @ 2.66GHz hw.ncpu: 4 hw.machine_arch: amd64 

HHD传输信息

 Seek times: Full stroke: 250 iter in 1.507837 sec = 6.031 msec Half stroke: 250 iter in 1.461401 sec = 5.846 msec Quarter stroke: 500 iter in 5.829283 sec = 11.659 msec Short forward: 400 iter in 2.668680 sec = 6.672 msec Short backward: 400 iter in 3.261849 sec = 8.155 msec Seq outer: 2048 iter in 0.247219 sec = 0.121 msec Seq inner: 2048 iter in 0.246036 sec = 0.120 msec Transfer rates: outside: 102400 kbytes in 1.207812 sec = 84781 kbytes/sec middle: 102400 kbytes in 1.342168 sec = 76294 kbytes/sec inside: 102400 kbytes in 1.893578 sec = 54078 kbytes/sec I/O command overhead: time to read 10MB block 0.131751 sec = 0.006 msec/sector time to read 20480 sectors 2.170542 sec = 0.106 msec/sector calculated command overhead = 0.100 msec/sector 

顶部（在负载高的时刻）

  Mem: 1518M Active, 1396M Inact, 732M Wired, 50M Cache, 435M Buf, 239M Free 4949 mysql 27 52 0 2236M 1434M uwait 3 180:02 66.26% mysqld 

my.cnf中

 [mysqld] sql_mode=NO_ENGINE_SUBSTITUTION skip-external-locking max_connections=5000 max_connect_errors=1500 ft_min_word_len = 2 myisam_sort_buffer_size = 64M # Log slow queries slow_query_log = 1 slow_query_log_file = /var/log/slow-queries.log long_query_time = 1 key_buffer = 384M max_allowed_packet = 32M thread_stack = 128K thread_cache_size = 128 thread_concurrency = 16 wait_timeout = 2000 interactive_timeout = 10000 join_buffer_size = 1M sort_buffer_size = 2M read_buffer_size = 1M read_rnd_buffer_size = 2M query_cache_size = 268435456 query_cache_type=1 query_cache_limit=1048576 

我不知道什么是错的。