Пересылка: Online Performance Tuning

["Shulzhenko Vasyl" <vasilis@softline.kiev.ua>]

-----Исходное сообщение-----
От: Sean Kelsey <chilliinc@hotmail.com>
Группы: comp.databases.informix
Дата: 29 января 1999 г. 14:50
Тема: Re: Online Performance Tuning


>Checkpoints taking time eh ??
>
>Number of things to look at:-
>
>1) The size of the Physical Log - checkpoints are issued if it becomes 75%
>full
>2) LRU_MAX_DIRTY & LRU_MIN_DIRTY. Both of these values determine when
>cleaner threads kick in and start to clean the dirty pages within the LRU
>buffers. They start when %age of dirty pages >= LRU_MAX_DIRTY and stop when
>%age of dirty pages<=LRU_MIN_DIRTY is reached. If these values are set quite
>low ( 10 & 5 or 5 & 3 respectively ) , then cleaner threads will clean dirty
>pages in between checkpoints.
>3) Length of time between checkpoints. Reduce the amount of time between
>chekpoints from 300 (default) to 120.
>
>These are just some of the many different configs that can alter the
>checkpoint duration.
>
>As far as the books go, Joe Lumbley's book is excellent (plug plug) and
>Informix Unleashed is great for an all-round perspective.
>
>Sean
>
>
>Dave McNight wrote in message <36B06F8A.357@bju.edu>...
>>I would like to get a better handle on Online Performance tuning. We
>>are running 7.3. We have a copy of "Informix-Online Performance Tuning"
>>by Elizabeth Suto the first edition. I noticed that the second edition
>>is available, but was published in 1996. Is there enough new information
>>in the 2nd edition to make it worth while? I am looking at ordering
>>"Informix Unleashed" and Joe Lumbley's new book. To recommend any
>>others?  Thanks ahead of time :-)) (Our checkpoints are running from 4
>>to 9 seconds; it would be nice to get that down to 2-4 seconds)
>>
>>Dave McNight
>>Bob Jones University
>>Unix/Informix Administrator
>
>