nginx 調整 buffer 以避免 502 bad gateway

nginx.conf

http {    
    proxy_buffer_size   128k;
    proxy_buffers   4 256k;
    proxy_busy_buffers_size   256k;

    fastcgi_buffer_size 128k;
    fastcgi_buffers 4 256k;
    fastcgi_busy_buffers_size 128k;
  
  ...
    
}