int PostmasterMain(int argc, char* argv[])
{
        ……
        gs_signal_slots_init(GLOBAL_ALL_PROCS + EXTERN_SLOTS_NUM);  //信号插槽初始化
        gs_signal_startup_siginfo("PostmasterMain");
        gs_signal_monitor_startup();
        ……
}

void gs_signal_slots_init(unsigned long int size)
{
    g_instance.signal_base->slots =
        (GsSignalSlot*)MemoryContextAlloc(t_thrd.mem_cxt.gs_signal_mem_cxt, (sizeof(GsSignalSlot) * size));

    /* create GsSignal for ever slot */
    g_instance.signal_base->slots_size = size;
    for (loop = 0; loop < g_instance.signal_base->slots_size; loop++) {
        int cnt_nodes = ((loop > 0) ? SUB_HODLER_SIZE : size);  // SUB_HODLER_SIZE = 100

        GsSignalSlot* tmp_sig_slot = tmp_sig_slot = &(g_instance.signal_base->slots[loop]);
        tmp_sig_slot->gssignal = gs_signal_init(cnt_nodes);
    }
}

static GsSignal* gs_signal_init(int cnt_nodes)
{
    GsSignal* gs_signal = (GsSignal*)MemoryContextAlloc(t_thrd.mem_cxt.gs_signal_mem_cxt, sizeof(struct GsSignal));
    gs_signal_sigpool_init(gs_signal, cnt_nodes);
    return gs_signal;
}

static void gs_signal_sigpool_init(GsSignal* gs_signal, int cnt_nodes)
{
    SignalPool* sigpool = &gs_signal->sig_pool;

    sigpool->free_head =
        (GsNode*)MemoryContextAlloc(t_thrd.mem_cxt.gs_signal_mem_cxt, (unsigned int)(cnt_nodes) * sizeof(GsNode));

    for (loop = 0; loop < (unsigned int)cnt_nodes - 1; loop++) {
        sigpool->free_head[loop].next = &(sigpool->free_head[loop + 1]);
    }
    sigpool->free_head[cnt_nodes - 1].next = NULL;

    sigpool->free_head = &sigpool->free_head[0];
    sigpool->free_tail = &sigpool->free_head[cnt_nodes - 1];
    sigpool->used_head = NULL;
    sigpool->used_tail = NULL;
    sigpool->pool_size = cnt_nodes;
}