LAMP – > Apache处理器的CPU使用率过高

我有一个LAMP系统与CentOS 6.4，Apache 2.2.15，MySQL 5.5.32和PHP 5.3.26与APC 3.1.10使用Drupal CMS（HTTPS）在一个虚拟机与4 CPU和6 GB的RAM。

我的问题是Apache进程的CPU使用率将达到100％，如果我做一个网页爬虫与10个并发请求。 我能做些什么来减lessCPU使用率？ 有任何想法吗？ 这里是我top server-status结果和configuration文件与mod_status server-status页面：

 top - 20:37:23 up 14 days, 22:52, 2 users, load average: 8.54, 6.45, 3.22 Tasks: 180 total, 8 running, 171 sleeping, 0 stopped, 1 zombie Cpu(s): 93.5%us, 6.2%sy, 0.0%ni, 0.0%id, 0.1%wa, 0.0%hi, 0.2%si, 0.0%st Mem: 8061508k total, 7634052k used, 427456k free, 146132k buffers Swap: 8208376k total, 35116k used, 8173260k free, 5019896k cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 13155 apache 20 0 472m 95m 41m R 69.8 1.2 0:04.75 httpd 13144 apache 20 0 467m 88m 40m R 61.8 1.1 0:03.49 httpd 13141 apache 20 0 477m 97m 39m R 52.9 1.2 0:06.69 httpd 13162 apache 20 0 449m 71m 41m R 51.5 0.9 0:04.53 httpd 13145 apache 20 0 473m 93m 39m R 30.6 1.2 0:02.13 httpd 13136 apache 20 0 477m 98m 40m R 28.9 1.3 0:04.93 httpd 13158 apache 20 0 459m 79m 38m S 28.9 1.0 0:00.87 httpd 13160 apache 20 0 467m 84m 36m R 24.9 1.1 0:00.75 httpd 3496 mysql 20 0 2454m 374m 5072 S 19.6 4.8 31:10.75 mysqld 13120 apache 20 0 460m 81m 40m S 15.3 1.0 0:05.63 httpd 13148 apache 20 0 462m 82m 39m R 12.0 1.1 0:01.79 httpd 

我在我的httpd.conf使用这个：

 Timeout 60 KeepAlive On MaxKeepAliveRequests 128 KeepAliveTimeout 10 <IfModule prefork.c> StartServers 16 MinSpareServers 10 MaxSpareServers 40 ServerLimit 256 MaxClients 256 MaxRequestsPerChild 4000 </IfModule> 

而这在我的MySQL my.cnf （其他是默认的）：

• 一个更慢/更大的VS两个更快/更小的RAM
• rmem_max超过rmem_default
• Linux：SSD性能调整队列
• 增加nginx活动连接超过65535
• 设置nginx工作人员的负面影响太高

 max_allowed_packet = 64M query_cache_size = 128M query_cache_type = 1 query_cache_limit= 1M slow-query-log-file=/var/log/mysqld/log-slow-queries.log // nothing logged -> no slow queries table_cache = 1K table_definition_cache = 4K open_files_limit = 3K thread_cache_size = 3 

如果服务器没有任何关系， mod_status显示了我这个：

 Parent Server Generation: 0 Server uptime: 23 seconds Total accesses: 10 - Total Traffic: 49 kB CPU Usage: u.04 s0 cu0 cs0 - .174% CPU load .435 requests/sec - 2181 B/second - 5017 B/request 1 requests currently being processed, 15 idle workers W_______________................................................ ................................................................ ................................................................ ................................................................ Scoreboard Key: "_" Waiting for Connection, "S" Starting up, "R" Reading Request, "W" Sending Reply, "K" Keepalive (read), "D" DNS Lookup, "C" Closing connection, "L" Logging, "G" Gracefully finishing, "I" Idle cleanup of worker, "." Open slot with no current process Srv PID Acc M CPU SS Req Conn Child Slot Client VHost Request 0-0 14223 10/10/10 W 0.04 0 0 49.1 0.05 0.05 IP www.test.com GET /server-status HTTP/1.1 

和一个网站爬虫（约10个并发请求）：

 Server uptime: 5 minutes 46 seconds Total accesses: 1883 - Total Traffic: 65.5 MB CPU Usage: u365.13 s17.79 cu0 cs0 - 111% CPU load 5.44 requests/sec - 193.8 kB/second - 35.6 kB/request 15 requests currently being processed, 10 idle workers WWWW_WWKW___W_W__WW__K_WW....................................... ................................................................ ................................................................ ................................................................ Srv PID Acc M CPU SS Req Conn Child Slot Client VHost Request 0-0 14223 90/207/207 W 2.07 0 0 902.0 1.61 1.61 IP www.test.com GET /server-status HTTP/1.1 1-0 14224 11/70/70 W 18.87 47 0 279.7 0.84 0.84 IP www.test.com GET /site1 2-0 14225 0/19/19 W 9.66 1 0 0.0 0.95 0.95 IP www.test.com GET /site2 3-0 14226 1/84/84 W 13.94 36 0 0.0 2.14 2.14 IP www.test.com GET /site3.pdf 4-0 14227 0/153/153 _ 27.46 4 81 0.0 3.56 3.56 IP www.test.com GET /site4pdf 5-0 14228 12/78/78 W 17.59 1 0 275.8 2.67 2.67 IP www.test.com GET /site5.pdf 6-0 14229 10/90/90 W 14.62 0 0 611.4 3.85 3.85 IP www.test.com GET /site6 7-0 14230 4/53/53 K 34.12 0 141 9 81.9 2.48 IP www.test.com GET /site7 8-0 14231 1/114/114 W 12.39 27 0 0.0 2.29 2.29 IP www.test.com GET /site8.pdf 9-0 14232 0/106/106 _ 9.68 2 64 0.0 6.33 6.33 IP www.test.com GET /site9 10-0 14233 0/39/39 _ 15.66 5 1376 0.0 2.68 2.68 IP www.test.com GET /site10 11-0 14234 0/36/36 _ 11.31 5 128 0.0 2.78 2.78 IP www.test.com GET /site11 12-0 14235 1/63/63 W 10.58 7 0 70.9 3.59 3.59 IP www.test.com GET /site12.pdf 13-0 14236 0/100/100 _ 22.76 1 20 0.0 2.76 2.76 IP www.test.com GET /site13 14-0 14237 0/63/63 W 4.34 37 0 0.0 0.58 0.58 IP www.test.com GET /site14 15-0 14238 0/12/12 _ 1.75 0 29 0.0 1.85 1.85 IP www.test.com GET /site15 16-0 14283 0/43/43 _ 14.94 1 119 0.0 2.25 2.25 IP www.test.com GET /site16 17-0 14286 8/80/80 W 6.79 0 0 222.7 5.98 5.98 IP www.test.com GET /site17.pdf 18-0 14288 3/111/111 W 21.87 0 0 60.5 2.35 2.35 IP www.test.com GET /site18.pdf 19-0 14289 0/75/75 _ 18.81 5 31 0.0 3.06 3.06 IP www.test.com GET /site19 20-0 14290 0/50/50 _ 16.15 1 259 0.0 2.16 2.16 IP www.test.com GET /site20.pdf 21-0 14292 6/88/88 K 23.71 0 0 32.8 2.79 2.79 IP www.test.com GET /site21 22-0 14293 0/92/92 _ 30.82 1 45 0.0 3.78 3.78 IP www.test.com GET /site22 23-0 14294 11/37/37 W 12.85 27 0 774.2 1.48 1.48 IP www.test.com GET /site23.pdf 24-0 14302 16/20/20 W 10.18 37 0 557.3 0.68 0.68 IP www.test.com GET /site24.pdf 

在爬行结束时，我已经达到Srv 46-0 。

Swappping？ 这是我在爬行完成后做的：

 # swapon -s Filename Type Size Used Priority /dev/am-1 partition 8208376 35172 -1 # free total used free shared buffers cached Mem: 8061508 7287776 773732 0 147220 4806004 -/+ buffers/cache: 2334552 5726956 Swap: 8208376 35172 8173204