and logical.name='session logical reads'; Buffer Cache Hit Ratio --- .906437759 3、获取推荐值 select name,size_for_estimate,v$db_cache_advice.ESTD_PHYSICAL_READS from v$db_cache_advice where block_size='8192' and advice_status='ON'; NAMESIZE_FOR_ESTIMATE ESTD_PHYSICAL_READS --- --- -...
2 where block_size='8192' and advice_status='ON'; 中,size_for_estimate表示预计的数据库高速缓冲区的大小(即:db_cache_size的值)。ESTD_PHYSICAL_READS表示预计的物理读。 当增加数据库高速缓冲区的的时候,物理读(ESTD_PHYSICAL_READS)越少,说明命中率越高。 1.优化缓冲区大小、提高服务器的命中率 db_c...