删除普通文件，以Unix Socket方式运行时，sock文件由php-fpm创建

配置文件不是写着了么，php-fpm会自己生成这个socket文件，并且被master进程所引用

; The address on which to accept FastCGI requests.
; Valid syntaxes are:
;   'ip.add.re.ss:port'    - to listen on a TCP socket to a specific IPv4 address on
;                            a specific port;
;   '[ip:6:addr:ess]:port' - to listen on a TCP socket to a specific IPv6 address on
;                            a specific port;
;   'port'                 - to listen on a TCP socket to all IPv4 addresses on a
;                            specific port;
;   '[::]:port'            - to listen on a TCP socket to all addresses
;                            (IPv6 and IPv4-mapped) on a specific port;
;   '/path/to/unix/socket' - to listen on a unix socket.

我感觉是配置写错了。

php-fpm.conf

listen = /dev/shm/php-fcgi.sock
listen.owner = www
listen.group = www
listen.mode = 0660

nginx.conf

fastcgi_pass unix:/dev/shm/php-fcgi.sock;