socket keep alive not working on Linux as expected

Question

I am using this code to setup a socket to detect a network error:

int socket_keepalive(int s, int ktime, int kinterval, int kprobes) {
    int enable = 1;
    if(setsockopt(s, SOL_SOCKET, SO_KEEPALIVE, &enable, sizeof(int)) < 0) {
            printf("setsockopt SO_KEEPALIVE failed (%s)\n", strerror(errno));
            return -1;
    }

    if(setsockopt(s, IPPROTO_TCP, TCP_KEEPIDLE, &ktime, sizeof(int) < 0)) {
            printf("setsockopt TCP_KEEPIDLE failed\n");
            perror("SO_KEEPALIVE: ");
            return -1;
    }

    if(setsockopt(s, IPPROTO_TCP, TCP_KEEPINTVL, &kinterval, sizeof(int) < 0)) {
            printf("setsockopt TCP_KEEPINTVL failed\n");
            perror("TCP_KEEPINTVL: ");
            return -1;
    }

    if(setsockopt(s, IPPROTO_TCP, TCP_KEEPCNT, &kprobes, sizeof(int) < 0)) {
            printf("setsockopt TCP_KEEPCNT failed\n");
            perror("TCP_KEEPCNT: ");
            return -1;
    }

    return 0;
}

I am calling the above function like this:

socket_keepalive(sock, 30, 10, 1);

I expect the socket to be disconnected after 40 seconds after a network error. However, it takes almost 170 seconds after a network error on the remote side.

Any idea what I am doing wrong?