配置多个 php-fpm 解决 502

Justering

青基会红包项目，增加php-fpm到四个后每秒请求数从90到了350

服务器在遇到高并发时nginx发起的连接数，远远超过了php-fpm所能处理的数目，导致端口（或socket）频繁被锁，造成堵塞，所以容易出现502错误。

那么我们可以给php-fpm开启多个实例解决高并发下nginx出现 502 的问题

这里以青基会红包项目作为演示，启用四个php-fpm实例，把php-fpm分为四部分，每部分各听一个端口或socket，这样就减少了lock，采用nginx的upstream负载均衡，轮询每个socket来处理请求。

1. 给每个pf增加配置文件

cd /usr/local/php/etc
cp php-fpm.conf php-fpm1.conf
cp php-fpm.conf php-fpm2.conf
cp php-fpm.conf php-fpm3.conf
vim php-fpm1.conf
# start php-fpm1.conf
[global]
# 修改处1
pid = /usr/local/php/var/run/php-fpm2.pid
error_log = /usr/local/php/var/log/php-fpm2.log
log_level = error
emergency_restart_threshold = 60
emergency_restart_interval = 40
[www]
# 修改处2
listen = /tmp/php-cgi2.sock
listen.backlog = 2048
listen.allowed_clients = 127.0.0.1
listen.owner = www
listen.group = www
listen.mode = 0666
user = www
group = www
pm = dynamic
pm.max_children = 600
;pm.start_servers = 225
pm.min_spare_servers = 8
pm.max_spare_servers = 16
request_terminate_timeout = 20
request_slowlog_timeout = 0
# 修改处3
slowlog = /usr/local/php/var/log/slow2.log
listen.allowed_clients = 127.0.0.1
pm.status_path = /xxxxxxfpmstatus
# end php-fpm1.conf

1. 增加进程

cd /etc/init.d/
cp php-fpm php-fpm1
cp php-fpm php-fpm2
cp php-fpm php-fpm3
vim php-fpm1
php_fpm_BIN=${exec_prefix}/sbin/php-fpm
php_fpm_CONF=${prefix}/etc/php-fpm1.conf # 修改处1，对应上面的配置文件
php_fpm_PID=${prefix}/var/run/php-fpm1.pid # 修改处2
service php-fpm1 start
service php-fpm2 start
service php-fpm3 start

1. 修改 nginx 的配置文件

# 在 http 块之后添加 phpbackend 是名字随便起
# 把 pf 配置到不同的机器上，就是正宗的负载均衡了
upstream phpbackend {
    # 可以选择分配模式 weight 权重，或者 ip_hash...
    server unix:/tmp/php-cgi.sock weight=100 max_fails=5 fail_timeout=5;
    server unix:/tmp/php-cgi1.sock weight=100 max_fails=5 fail_timeout=5;
    server unix:/tmp/php-cgi2.sock weight=100 max_fails=5 fail_timeout=5;
    server unix:/tmp/php-cgi3.sock weight=100 max_fails=5 fail_timeout=5;
}

1. 修改应用的 vhost 配置

vim vhost/hb_test.conf
server
{
    listen 80;
    server_name 182.92.68.139;
    index index.html index.htm index.php;
    root  /home/wwwroot/cydf_hongbao_test;
    include /home/wwwroot/cydf_hongbao_test/nginx_rewrite.conf;
    location ~ .*\.(php|php5)?$
        {
            try_files $uri =404;
            # 修改为上面配置的 upstream
            fastcgi_pass phpbackend;
            # fastcgi_pass unix:/tmp/php-cgi.sock;
            fastcgi_index index.php;
            include  fastcgi.conf;
        }
    location ~ .*\.(gif|jpg|jpeg|png|bmp|swf)$
        {
            expires      30d;
        }
    location ~ .*\.(js|css)?$
        {
            expires      12h;
        }
    access_log  /home/wwwlogs/hongbao_test-access.log  access;
    error_log /home/wwwlogs/hongbao_test-error.log error;
}