Re: partition buffer summary - Btree percentage

Doug, good luck with the stress tests - I would be interested to hear how it goes. The version I have is 7.30.UC7XM and seems ok so far. I think the interim 7.30 release with the fix is 7.30.UC10 - which isn't out yet. Pete Logica In article <6uPF3.2929$9W2.5801@news2.mco>, "Doug Agnew" <dagnew@charlottepipe.com> wrote: > It is sorta fixed in 7.30UC7 --- we are using version 7.30UC7XK1, and it > seems to be okay there (at least our small test system didn't show the > buffer problem). Will probably be stressing it this week as we upgrade > SAP.... > > Doug > > Art S. Kagel wrote in message <37E7BA3B.DC191AA1@bloomberg.net>... > >I believe it is fixed in 7.31UC3 and 7.30UC7, I relocated my desk and > >cannot find the note on the subject so I'm going from memory here. I do > >not think there is a fix contemplated for 7.2x so upgrades MAY have to > >rebuild indexes to eliminate the problem. > > > >Art S. Kagel > > > >"Carlson@WHSmith" wrote: > >> > >> Any idea in which version this bug is fixed? > >> > >> John Carlson > >> Informix DBA > >> WHSmith USA > >> > >> plsmith@my-deja.com wrote: > >> > > >> > Vardan > >> > > >> > You have almost certainly run into bug no. 115327 and you should be > >> > able to request a patch to fix it. > >> > It is a bug in 7.2x and 7.3x whereby btree pages can be generated with > >> > an invalid page type. This page type is then handled incorrectly by the > >> > new 7.30 buffer priority management. > >> > Dropping and rebuilding affected indexes is a reasonable workaround, > but > >> > the problme could re-occur depending on the habits of you application. > >> > The invalid page types are generated when all the rows are deleted from > >> > a table thus compressing the index down to a single page. When rows are > >> > inserted an invalid page type is then copied through all the leaf > nodes. > >> > If you look at onstat -R you will see that the majority of pages are in > >> > the medium-high category, whereas data pages are medium-low. Leaf node > >> > pages should also be medium low, but because of the invalid page type > >> > they are placed in the medium-high category, thus squeezing out the > data > >> > pages. If you install a patch you should see a reversal of these > >> > percentages and an increase in your read cache. > >> > If you talk to Informix tech support refer them to case No. 861366 > which > >> > contains a reproducable example. > >> > I have a small script which will identify invalid pages types (sql > >> > courtesy of John Miller, thanks ). > >> > > >> > email me if you would like a copy. > >> > > >> > hth > >> > Pete Smith > >> > Logica > >> > > >> > In article <7s5n3g$mq7$1@nnrp1.deja.com>, > >> > Vardan Aroustamian <vaar@geocities.com> wrote: > >> > > Hello, > >> > > > >> > > I'm new to SAP environment and would like to get some input > >> > > from experienced users. > >> > > > >> > > Anyone knows of some "usual" percentage for Data vs. Btree > >> > > pages in the buffer pool (from onstat -P output). > >> > > > >> > > Currently I have > >> > > > >> > > Percentages: > >> > > Data 20.09 > >> > > Btree 77.75 > >> > > Other 2.16 > >> > > > >> > > I heard about some bug when Btree is more than 90%. > >> > > I'm not sure will I reach that number. > >> > > > >> > > Informix 7.30.UC7XB > >> > > SunOS 5.5.1 > >> > > > >> > > Database ~50GB > >> > > SAP 4.5 > >> > > > >> > > Actually I believe this is not SAP specific question. > >> > > Anyway, thanks for any information. > >> > > > >> > > Vardan > >> > > > >> > > -- > >> > > Vardan Aroustamian > >> > > vaar@geocities.com > >> > > > >> > > Sent via Deja.com http://www.deja.com/ > >> > > Share what you know. Learn what you don't. > >> > > > >> > > >> > Sent via Deja.com http://www.deja.com/ > >> > Share what you know. Learn what you don't. > > Sent via Deja.com http://www.deja.com/ Share what you know. Learn what you don't.