56.Oracle杂记——Oracle常用动态视图v$db_cache_advice

视图v$db_cache_advice的每行显示        CACHE大小下,物理读次数。

描述如下:

idle> desc v$db_cache_advice;

 Name                                                                  Null?    Type

 ------------------------------------------------------------- ------------------------------------

 ID                                                                             NUMBER

 NAME                                                                               VARCHAR2(20)

 BLOCK_SIZE                                                                    NUMBER

 ADVICE_STATUS                                                                     VARCHAR2(3)

 SIZE_FOR_ESTIMATE                                                           NUMBER

 SIZE_FACTOR                                                                NUMBER

 BUFFERS_FOR_ESTIMATE                                                            NUMBER

 ESTD_PHYSICAL_READ_FACTOR                                                NUMBER

 ESTD_PHYSICAL_READS                                                       NUMBER

 ESTD_PHYSICAL_READ_TIME                                           NUMBER

 ESTD_PCT_OF_DB_TIME_FOR_READS                                              NUMBER

 ESTD_CLUSTER_READS                                                        NUMBER

 ESTD_CLUSTER_READ_TIME                                                      NUMBER

 CON_ID                                                                           NUMBER

各个列含义如下:

ID:缓存尺的ID(从1到8)

 NAME:缓冲池的名字

 BLOCK_SIZE:缓存池的块大小

 ADVICE_STATUS:资讯状态

 SIZE_FOR_ESTIMATE:评估的CACHE大小(MB)

 SIZE_FACTOR:和当前大小的比例

 BUFFERS_FOR_ESTIMATE:评估的CACHE大小(BUFFERS)

 ESTD_PHYSICAL_READ_FACTOR:当前CACHE下预测的物理读和实际CACHE大小的物理读

 ESTD_PHYSICAL_READS:当前CACHE下预测的物理读

 ESTD_PHYSICAL_READ_TIME:读磁盘的估计时间

 ESTD_PCT_OF_DB_TIME_FOR_READS:花费在磁盘的时间百分比

 ESTD_CLUSTER_READS:前台进程从GC上读的次数

 ESTD_CLUSTER_READ_TIME:前台进程从GC上读的时间

 CON_ID :容器ID