我在具有以下配置的服务器上：
32 GB RAM 12 核处理器
它在 nginx、varnish、php5-fpm、fastcgi 上运行单个 wordpress。一切都运行良好，但昨天晚上之后，整个网站突然变得非常慢，没有响应。经过检查，我发现 mysql 占用了大量 CPU。在网上搜索了很多资料后，我禁用了 XML-RPC，mysql 的 CPU 负载大幅下降。
但问题仍然存在，我的 CPU 几乎 100%。我发现 php5-fpm 进程占用了所有的 CPU。
这是 top 的结果
top - 10:30:33 up 7:10, 1 user, load average: 31.35, 31.87, 31.85
Tasks: 238 total, 27 running, 179 sleeping, 32 stopped, 0 zombie
%Cpu(s): 84.9 us, 11.7 sy, 0.0 ni, 3.1 id, 0.0 wa, 0.0 hi, 0.3 si, 0.0 st
KiB Mem: 32948544 total, 11695168 used, 21253376 free, 408404 buffers
KiB Swap: 0 total, 0 used, 0 free. 3151748 cached Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
12179 mysql 20 0 6233684 998836 7632 S 109.2 3.0 371:56.58 mysqld
18533 nginx 20 0 1007708 769740 26008 R 57.5 2.3 3:33.24 php5-fpm
18487 nginx 20 0 600672 361312 26212 R 51.7 1.1 4:13.51 php5-fpm
18657 nginx 20 0 280024 42640 25436 R 51.7 0.1 0:46.94 php5-fpm
18459 nginx 20 0 996592 753804 25764 R 40.2 2.3 4:53.79 php5-fpm
18469 nginx 20 0 1010296 768676 25704 R 40.2 2.3 4:22.98 php5-fpm
18545 nginx 20 0 277216 40060 25740 R 40.2 0.1 2:53.74 php5-fpm
18547 nginx 20 0 684952 441796 25616 R 40.2 1.3 2:58.57 php5-fpm
18629 nginx 20 0 280452 42752 25444 R 40.2 0.1 1:22.99 php5-fpm
18460 nginx 20 0 282796 45920 25828 R 34.5 0.1 5:22.28 php5-fpm
18461 nginx 20 0 276952 40200 25636 R 34.5 0.1 4:13.64 php5-fpm
18462 nginx 20 0 278752 41504 25672 R 34.5 0.1 4:16.16 php5-fpm
18540 nginx 20 0 277744 41096 25740 R 34.5 0.1 3:02.92 php5-fpm
18624 nginx 20 0 278648 41060 25588 R 34.5 0.1 1:27.54 php5-fpm
18452 nginx 20 0 278752 41696 25732 S 28.7 0.1 4:25.82 php5-fpm
18458 nginx 20 0 282488 45512 25684 S 28.7 0.1 4:44.26 php5-fpm
18472 nginx 20 0 282652 45976 25948 R 28.7 0.1 4:34.61 php5-fpm
18486 nginx 20 0 1007732 769472 25800 R 28.7 2.3 4:03.61 php5-fpm
18491 nginx 20 0 282488 45584 25764 R 28.7 0.1 4:06.75 php5-fpm
18495 nginx 20 0 280744 43216 25744 R 28.7 0.1 3:37.82 php5-fpm
18496 nginx 20 0 282488 44924 25908 R 28.7 0.1 3:38.28 php5-fpm
18562 nginx 20 0 282488 45412 25584 R 28.7 0.1 2:53.19 php5-fpm
18575 nginx 20 0 282760 46068 26192 R 28.7 0.1 2:34.81 php5-fpm
18455 nginx 20 0 278904 41532 25716 S 23.0 0.1 4:22.13 php5-fpm
18468 nginx 20 0 278776 42120 25732 R 23.0 0.1 4:09.41 php5-fpm
18490 nginx 20 0 280840 44148 26172 R 23.0 0.1 3:39.08 php5-fpm
18492 nginx 20 0 282232 45260 25652 R 23.0 0.1 4:07.21 php5-fpm
18514 nginx 20 0 282608 45716 25732 R 23.0 0.1 3:44.15 php5-fpm
18576 nginx 20 0 279416 41964 25496 R 23.0 0.1 2:09.75 php5-fpm
18656 nginx 20 0 279560 42428 25508 S 23.0 0.1 0:49.84 php5-fpm
18465 nginx 20 0 284492 47860 26252 R 17.2 0.1 5:09.60 php5-fpm
10165 nobody 20 0 11.233g 2.437g 83232 S 11.5 7.8 23:56.78 varnishd
18686 root 20 0 24948 1656 1080 R 11.5 0.0 0:00.04 top
8 root 20 0 0 0 0 S 5.7 0.0 2:48.56 rcuos/0
18122 nginx 20 0 36700 7428 1040 S 5.7 0.0 1:04.16 nginx
18129 nginx 20 0 33836 4568 1040 S 5.7 0.0 0:25.52 nginx
如您所见，平均负载非常高，是31.35, 31.87, 31.85
什么导致 CPU 使用率如此之高。我尝试过调整从 mysql 到 nginx 再到 varnish 的所有东西，但似乎都不起作用。我也尝试过pm在我的php5 conf文件中调整值，但在这里，我却抓狂不已。
请帮忙。
该网站的流量很大，平均有 2000 到 3000 个并发用户。:(
更新：
包括 nginx conf 文件： /etc/nginx/nginx.conf
user nginx;
worker_processes 12;
worker_rlimit_nofile 20000;
error_log /var/log/nginx/error.log warn;
pid /var/run/nginx.pid;
events {
worker_connections 3000;
use epoll;
multi_accept on;
}
http {
server_names_hash_bucket_size 64;
include /etc/nginx/mime.types;
default_type application/octet-stream;
log_format main '$remote_addr - $remote_user [$time_local] "$request" '
'$status $body_bytes_sent "$http_referer" '
'"$http_user_agent" "$http_x_forwarded_for"';
access_log /var/log/nginx/access.log main;
limit_req_zone $binary_remote_addr zone=one:100m rate=3r/m;
sendfile on;
tcp_nopush on;
tcp_nodelay on;
keepalive_timeout 65;
client_header_timeout 180;
client_body_timeout 180;
fastcgi_read_timeout 180;
client_body_buffer_size 10M;
client_max_body_size 32m;
gzip on;
gzip_disable "msie6";
gzip_vary on;
gzip_proxied any;
gzip_comp_level 6;
gzip_buffers 16 8k;
gzip_http_version 1.1;
gzip_types text/plain text/css application/json application/x-javascript text/xml application/xml application/xml+rss text/javascript;
include /etc/nginx/conf.d/*.conf;
port_in_redirect off;
}
/etc/nginx/conf.d/默认.conf
server {
listen 8080;
server_name mysite.com;
return 301 $scheme://www.mysite.com$request_uri;
}
server {
## Your website name goes here.
server_name www.mysite.com;
## Your only path reference.
root /var/www/;
listen 8080;
## This should be in your http block and if it is, it's not needed here.
index index.html index.htm index.php;
include conf.d/drop;
location / {
# This is cool because no php is touched for static content
try_files $uri $uri/ /index.php?q=$uri&$args;
}
location ~ \.php$ {
try_files $uri =404;
# proxy buffers - no 502 errors!
proxy_buffer_size 128k;
proxy_buffers 4 256k;
proxy_busy_buffers_size 256k;
fastcgi_buffers 256 16k;
fastcgi_buffer_size 128k;
fastcgi_max_temp_file_size 0;
fastcgi_intercept_errors on;
include fastcgi_params;
fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
fastcgi_pass unix:/dev/shm/php-fpm-www.sock;
#fastcgi_pass 127.0.0.1:9000;
location ~* wp\-login\.php {
limit_req zone=one burst=1 nodelay;
include fastcgi_params;
fastcgi_pass unix:/dev/shm/php-fpm-www.sock;
}
}
location /xmlrpc.php {
deny all;
}
}
答案1
从另一个角度来看，我注意到了一些东西。如果你不使用 Memcache，你就不需要 Varnish。Varnish 是“pasato”，因为它不打算支持韋斯迪正如 Varnish 的作者曾经说过的那样，已经很长时间了。
我还看到您的缓存层实际上位于应用程序层。您正在使用 W3TC 插件。
您仍然可以添加配置。我还没有看到。
location ~* \.(jpg|jpeg|png|gif|ico|css|js)$ {
expires 365d;
}
还可以改进您在网络服务器上允许的内容。
## Only allow these request methods ##
if ($request_method !~ ^(GET|HEAD|POST)$ ) {
return 444;
}
## Do not accept DELETE, SEARCH and other methods ##