nginx: [emerg] "check_shm_size" directive is duplicate

[developKmv]

Good afternoon.

I try to use check_shm_size directive and get a fail while check a config via
nginx-t

nginx: [emerg] "check_shm_size" directive is duplicate in /etc/nginx/tcp.conf:2
nginx: configuration file /etc/nginx/nginx.conf test failed

/etc/nginx/tcp.conf
tcp {
check_shm_size 128k;
access_log /var/log/nginx/tcp_access.log;
include /etc/nginx/tcp.conf.d/*;
}

How to use check_shm_size ?