函数buf_pool_init_instance

 

 buff_pool_t 结构体 详见

/********************************************************************//**
Initialize a buffer pool instance.
@return DB_SUCCESS if all goes well. */
UNIV_INTERN
ulint
buf_pool_init_instance(
/*===================*/
    buf_pool_t*    buf_pool,    /*!< in: buffer pool instance */
    ulint        buf_pool_size,    /*!< in: size in bytes */
    ulint        instance_no)    /*!< in: id of the instance */
{
    ulint        i;
    buf_chunk_t*    chunk;

    /* 1. Initialize general fields
    ------------------------------- */
    mutex_create(buf_pool_mutex_key,
             &buf_pool->mutex, SYNC_BUF_POOL);
    mutex_create(buf_pool_zip_mutex_key,
             &buf_pool->zip_mutex, SYNC_BUF_BLOCK);

    buf_pool_mutex_enter(buf_pool);

    if (buf_pool_size > 0) {
        buf_pool->n_chunks = 1;
        buf_pool->chunks = chunk = mem_zalloc(sizeof *chunk);

        UT_LIST_INIT(buf_pool->free);
        /**
 *为chunk->mem分配buf_pool_size大小的内存,该内存大小须能被16K整除
 *每16K对应一个frame,也对应一个控制chunk
 */ if (!buf_chunk_init(buf_pool, chunk, buf_pool_size)) { //详见
            mem_free(chunk);
            mem_free(buf_pool);

            buf_pool_mutex_exit(buf_pool);

            return(DB_ERROR);
        }

        buf_pool->instance_no = instance_no;
        buf_pool->old_pool_size = buf_pool_size;
        buf_pool->curr_size = chunk->size;
        buf_pool->curr_pool_size = buf_pool->curr_size * UNIV_PAGE_SIZE;

        buf_pool->page_hash = hash_create(2 * buf_pool->curr_size);
        buf_pool->zip_hash = hash_create(2 * buf_pool->curr_size);

        buf_pool->last_printout_time = ut_time();
    }
    /* 2. Initialize flushing fields
    -------------------------------- */

    mutex_create(flush_list_mutex_key, &buf_pool->flush_list_mutex,
             SYNC_BUF_FLUSH_LIST);

    for (i = BUF_FLUSH_LRU; i < BUF_FLUSH_N_TYPES; i++) {
        buf_pool->no_flush[i] = os_event_create(NULL);
    }

    /* 3. Initialize LRU fields
    --------------------------- */

    /* All fields are initialized by mem_zalloc(). */

    buf_pool_mutex_exit(buf_pool);

    return(DB_SUCCESS);
}