函数buf_pool_init

/********************************************************************//**
Creates the buffer pool.
@return    DB_SUCCESS if success, DB_ERROR if not enough memory or error */
UNIV_INTERN
ulint
buf_pool_init(
/*==========*/
    ulint    total_size,    /*!< in: size of the total pool in bytes */
    ulint    n_instances)    /*!< in: number of instances */
{
    ulint        i;
    //n_instances 一般为1
    const ulint    size    = total_size / n_instances;

    ut_ad(n_instances > 0);
    ut_ad(n_instances <= MAX_BUFFER_POOLS); //#define MAX_BUFFER_POOLS (1 << MAX_BUFFER_POOLS_BITS) 1<<6
    ut_ad(n_instances == srv_buf_pool_instances);

    /* We create an extra buffer pool instance, this instance is used
    for flushing the flush lists, to keep track of n_flush for all
    the buffer pools and also used as a waiting object during flushing. */
  
    //UNIV_INTERN buf_pool_t* buf_pool_ptr; 通过heap heap = mem_heap_create_func(n, MEM_HEAP_DYNAMIC, file_name, line); 实现 详见
    buf_pool_ptr = mem_zalloc(n_instances * sizeof *buf_pool_ptr);

    for (i = 0; i < n_instances; i++) {
        buf_pool_t*    ptr    = &buf_pool_ptr[i];

        if (buf_pool_init_instance(ptr, size, i) != DB_SUCCESS) { //详见

        /* Free all the instances created so far. */
            buf_pool_free(i);

            return(DB_ERROR);
        }
    }

    buf_pool_set_sizes();
    buf_LRU_old_ratio_update(100 * 3/ 8, FALSE);

    btr_search_sys_create(buf_pool_get_curr_size() / sizeof(void*) / 64);

    return(DB_SUCCESS);
}