WordPress服务器内存占用异常求助：请求协助定位问题根源

我已经花了好长时间排查这个问题，实在没法接受WordPress在常规使用场景下就把服务器资源跑满了，怀疑系统存在异常情况，恳请各位帮忙定位问题根源！

首先，我多次捕捉到这样的服务器资源使用快照：

PID CMD TID CPU MEM IO IOPS 
151698 /usr/local/apache/bin/httpd -k start -DSSL 0% 95 
151699 /usr/local/apache/bin/httpd -k start -DSSL 0% 95 
151700 /usr/local/apache/bin/httpd -k start -DSSL 0% 95 
151703 /usr/local/apache/bin/httpd -k start -DSSL 0% 95 
151709 /usr/local/apache/bin/httpd -k start -DSSL 0% 95 
151715 /usr/local/apache/bin/httpd -k start -DSSL 0% 95 
151758 /usr/local/apache/bin/httpd -k start -DSSL 0% 97 
151760 /usr/local/apache/bin/httpd -k start -DSSL 0% 97 
156720 /usr/local/apache/bin/httpd -k start -DSSL 0% 111 
156726 /usr/local/apache/bin/httpd -k start -DSSL 0% 111 
156731 /usr/local/apache/bin/httpd -k start -DSSL 0% 111 
156737 /usr/local/apache/bin/httpd -k start -DSSL 0% 111 
156738 /usr/local/apache/bin/httpd -k start -DSSL 0% 111 
156740 /usr/local/apache/bin/httpd -k start -DSSL 0% 111 
156743 /usr/local/apache/bin/httpd -k start -DSSL 0% 111 
156757 /usr/local/apache/bin/httpd -k start -DSSL 0% 117 
156761 /usr/local/apache/bin/httpd -k start -DSSL 0% 117 
156762 /usr/local/apache/bin/httpd -k start -DSSL 0% 117 
156763 /usr/local/apache/bin/httpd -k start -DSSL 0% 117 
156777 /usr/local/apache/bin/httpd -k start -DSSL 0% 117 
156780 /usr/local/apache/bin/httpd -k start -DSSL 0% 97 
156785 /usr/local/apache/bin/httpd -k start -DSSL 0% 97 
156786 /usr/local/apache/bin/httpd -k start -DSSL 0% 97 
156792 /usr/local/apache/bin/httpd -k start -DSSL 0% 97 
156798 /usr/local/apache/bin/httpd -k start -DSSL 0% 97 
281957 /usr/local/apache/bin/httpd -k start -DSSL 0% 79 
281975 /usr/local/apache/bin/httpd -k start -DSSL 0% 79 
281978 /usr/local/apache/bin/httpd -k start -DSSL 0% 79 
281980 /usr/local/apache/bin/httpd -k start -DSSL 0% 79 
282026 /usr/local/apache/bin/httpd -k start -DSSL 0% 79 
282027 /usr/local/apache/bin/httpd -k start -DSSL 0% 79 
282032 /usr/local/apache/bin/httpd -k start -DSSL 0% 79 
282041 /usr/local/apache/bin/httpd -k start -DSSL 0% 79 
282050 /usr/local/apache/bin/httpd -k start -DSSL 0% 79 
282059 /usr/local/apache/bin/httpd -k start -DSSL 0% 79 
310847 /usr/bin/php 0% 30 
310864 /usr/bin/php 0% 30 
311101 /usr/bin/php 0% 24 
311118 /usr/bin/php 0% 24 
311158 /usr/bin/php 0% 23 
311171 /usr/bin/php 0% 22 
311223 /usr/bin/php 1% 23 
311244 /usr/bin/php 0% 22 
312142 /usr/bin/php 0% 19 
312154 /usr/bin/php 0% 19 
312214 /usr/bin/php 0% 18 
312224 /usr/bin/php 1% 18 
312263 /usr/bin/php 1% 16 
312277 /usr/bin/php 0% 16 
312352 /usr/bin/php 1% 16 
312375 /usr/bin/php 0% 16 
312440 /usr/bin/php 1% 15 
312451 /usr/bin/php 0% 15 
312474 /usr/bin/php 0% 13 
312481 /usr/bin/php 0% 13 
312950 /usr/bin/php 0% 13 
313298 /usr/bin/php 0% 13 
313331 /usr/bin/php 1% 10 
313344 /usr/bin/php 1% 10 
313377 /usr/bin/php 1% 10 
313396 /usr/bin/php 0% 10 
313427 /usr/bin/php 0% 8 
313448 /usr/bin/php 0% 8 
313491 /usr/bin/php 1% 7 
313552 /usr/bin/php 1% 7 
313601 /usr/bin/php 1% 7 
313611 /usr/bin/php 1% 5 

此外，我的Cpanel网站统计数据如下：

我自己也在尝试各种方法解决，但还是希望能得到各位的技术协助！

内容的提问来源于stack exchange，提问作者Brandyn M Scott