Cognos优化

按默认设置，从Oracle抽取数据的速度较慢（即生成Cube的速度较慢）。如要提高速度，需修改默认配置（以Cognos 7.1为例）：

Cognos优化

1. 从Oracle数据集市中抽取数据

按默认设置，从Oracle抽取数据的速度较慢（即生成Cube的速度较慢）。如要提高速度，需修改默认配置（以Cognos 7.1为例）：

打开Installation LocationCognoscer3bincogdmor.ini文件，

Cognos优化: 找到如下文本行：

; The entry 'Fetch Buffer Size' is used to determine the size of buffer to

; use when fetching. Larger values can provide better performance on

; some systems. Note that on 16bit Windows platforms, this is restricted

; to approximately 64k.

;

; If both 'Fetch Buffer Size' and 'Fetch Number of Rows' are set, the latter

; will take precedence and the former will be ignored.

;

; By default, the buffer size used is 2048 bytes, to change this default,

; uncomment one of the following entries and set it accordingly.

;Fetch Buffer Size=2048

;Fetch Number of Rows=10

去掉黄色行的注释，并修改其值。

2. 抽取数据时Cognos服务器端的设置

为了提高生成Cube的速度，还需要配置Cognos的数据服务器，这需要结合当前机器的性能，修改默认配置（以Cognos 7.1为例）：

打开Installation LocationCognoscer3bincer3.ini文件，

1) 找到Section： PowerPlay DataServer，默认如下：

Cognos优化: [Services]

Cognos优化: SORTMEMORY=512

Cognos优化: 可将其修改为如下：

Cognos优化: [Services]

Cognos优化: SORTMEMORY=51200

2) 找到Section： PowerPlay DataServer，默认如下：

[PowerPlay DataServer]

Cognos优化: WriteCacheSize=4096

Cognos优化: ReadCacheSize=4096

Cognos优化: ObjectCacheSize=4096

Cognos优化: FlushPercentage=500

Cognos优化: 可将其修改为如下：

[PowerPlay DataServer]

WriteCacheSize=102400

Cognos优化: ReadCacheSize=8192

Cognos优化: ObjectCacheSize=4096

Cognos优化: FlushPercentage=500