Function getClientOutputBufferMemoryUsage

app/redis-6.2.6/src/networking.c:3169–3172

This function returns the number of bytes that Redis is * using to store the reply still not read by the client. * * Note: this function is very fast so can be called as many time as * the caller wishes. The main usage of this function currently is * enforcing the client output length limits. */

 * the caller wishes. The main usage of this function currently is
 * enforcing the client output length limits. */
unsigned long getClientOutputBufferMemoryUsage(client *c) {
    unsigned long list_item_size = sizeof(listNode) + sizeof(clientReplyBlock);
    return c->reply_bytes + (list_item_size*listLength(c->reply));
}

/* Get the class of a client, used in order to enforce limits to different
 * classes of clients.