Redis [BUG] IO threads not work well in many fds which are need to reply。such as feed 100 replicas

Describe the bug

when we have many fds need to reply。 clientHasPendingReplies always return 1. so clients do not add to client_pending_write list ，instead of AE_WRITE event。 in this case handleClientsWithPendingWritesUsingThreads does not work。 To reproduce int prepareClientToWrite(client *c) { if (!clientHasPendingReplies(c) && io_threads_op == IO_THREADS_OP_IDLE) clientInstallWriteHandler(c);

/* Authorize the caller to queue in the output buffer of this client. */
return C_OK;

}

Expected behavior

Additional information

here is my patch::

int prepareClientToWrite(client *c) {

if (!clientHasPendingReplies(c)) {
    serverLog(LL_DEBUG," client %s flags %lld no data, need to add clients_pending_write %d  ",
        c->name==NULL ? "NA" : (char*)c->name->ptr,c->flags,
        (int)listLength(server.clients_pending_write));
    if (io_threads_op  == IO_THREADS_OP_IDLE) {
        clientInstallWriteHandler(c);
    }

} else {
    serverLog(LL_DEBUG," client %s flags %lld have data,  clients_pending_write %d  ",
        c->name==NULL ? "NA" : (char*)c->name->ptr,c->flags,
        (int)listLength(server.clients_pending_write));

     int events = aeGetFileEvents(server.el,c->conn->fd);
     if ((events & AE_WRITABLE) && aeWait(c->conn->fd,AE_WRITABLE,0)) {
         serverLog(LL_DEBUG," %s hasAE_WRITABLE  socket writeable delAE_WRITABLE add clients_pending_write", 
             c->name==NULL ? "NA" : (char*)c->name->ptr);        
         connSetWriteHandler(c->conn, NULL);
         clientInstallWriteHandler(c);
     }
}
/* Authorize the caller to queue in the output buffer of this client. */
return C_OK;

}