Sybase 调优问题（内存与磁盘 I/O）

1017of

number of oam trips = 1024
why give this value so big?

1017of

原帖由 gugong 于 2006-1-9 10:23 发表


改为 DEFAULT ，还是一样啊。

大内存没有起到任何好处啊，唉，郁闷。

I suggest you change it into default unless you have an unique system.too big this value could make cache contain almost amount of oam pages,so data pages could not have enough cache pages to hold on,then lots of  I/Os could happens.
I'm still wondering why you give this value so big.in general,2 is too big to fit most systems,moreover 1024 is difficult to image.0,the default is fit for almost most systems.

[ 本帖最后由 1017of 于 2006-1-9 10:49 编辑 ]

1017of

wow,how complex the sql is.as you decribed above,first execution,some large table did more physical I/Os than second time.SQL Server elapsed time in second time fell into 4323 ms probably because less physical happened.I am not clear what you try to say.
btw:don't give such complex sql to ASE, sometime it will fail to get it work efficiently.