Re: Page cleaners

jasonharris@my-dejanews.com wrote: > > All, > > I have one question about page cleaners. As they run on CPU VP threads what is > the value in having more page cleaners that CPU VP threads? You need to look at a number of concepts to answer that. None of which I'm going to detail, but might include: the concepts of multi-threading the number of disks the throughput of the disks the order of chunk creation etc. However, what I wanted to say was; the rules for version 6 and upward as far as I know, are as follows: Configure at least one page cleaner thread per LRU queue pair. Which begs the question......... how many LRU queue pairs? Configure 4 LRU queue pairs per CPUVP. Which begs....... OLTP: Configure N-1 CPUVPs, where N=no. of CPUs DSS or DB server: Configure N CPUVPs, where N=no. of CPUs As with all tuning rules, these are very generalistic, and should be taken in the context of your environment. [This last comment was sponsored by the forum for reducing net traffic, just in case someone decides to detail the exceptions to the rules :] Cheers, -- Mark. +----------------------------------------------------------+-----------+ |Mark D. Stock - Informix SA http://www.informix.com |//////// /| |mailto:mdstock@informix.com http://www.informix.com/idn |///// / //| |http://www.iiug.org +-----------------------------------+//// / ///| | Tel: +27 11 807 0313 |If it's slow, the users complain. |/// / ////| | Fax: +27 11 807 2594 |If it's fast, the users keep quiet.|// / /////| |Cell: +27 83 250 2325 |Therefore, "No news: travels fast"!|/ ////////| +----------------------+-----------------------------------+-----------+