internal

关于Partial write for all MySQL and Oracle

September 2, 2014 Internals, MYSQL, oracle No comments

很久之前看过这个帖子,当时没有细究,这几天看了下mysql相关的internal 突然想起这个问题,跟三四个朋友讨论了下 想把这个问题展开讲一讲。

源帖子内容见:https://community.oracle.com/thread/1087650?start=0&tstart=0

这个[……]

Read more

How to control CF calculation

May 14, 2013 Internals, oracle No comments

根据Richard Foote的文章,做了如下验证:

RefClustering Factor Calculation Improvement and provide some control over DBMS_STATS index clustering factor computat[……]

Read more

Active dataguard tips

January 23, 2013 oracle, replication No comments

11g ADG 给了大家更多的灾备选择,包括之前美国飓风,给了ADG大放光彩的机会,但是ADG并没有想象中的那么完美,以下是最近的一个CASE,具体过程不详写了,目前这个case还在跟进中,记录之:

[oracle@dcb-srv-0174 trace]$ cat itemstd02_ora_[......]

Read more

Capture binds always actually ?

August 28, 2012 Internals, oracle No comments

我们可以通过v$sql_bind_capture 捕获到 bind values 这篇文章主要阐述v$sql_bind_capture与v$sql_plan的一些联系

SQL*Plus: Release 11.2.0.3.0 Production on Tue Aug 28 14:07[......]

Read more

some change in cache buffer handle

June 7, 2012 Internals, oracle No comments

今天开发因为连接数不够 强烈要求加大processes值,突然想到了processes对_cursor_db_buffers_pinned的影响,,小记之:

当会话需要pin住buffer header时它首先要获去buffer handle,实例所存在的buffer handle总数由(ea[……]

Read more

Oracle latch internals

June 6, 2012 Internals, oracle 4 comments

Oracle latch internals

Server latch implementation called KSL, e.g. every table with name starting with x$ksl… is latch
related and every[……]

Read more