Hi all ,
I have a strange problem to submit to the community.
We have an application (software developed by another company) in data sharing (4 members) from CICS transactions in CICS plex configuration. Transactions uses a table as temporary storage, create rows in it , some other read the rows and delete when finished. The key is something like Terminal ID, a business field and a sequence member. the data zone is varchar 30K.
The underlying TS is an UTS PBG 32K table, only one 2G partition used, MAXPART 1. It is in a quite preserved 32K bufferpool and during my trace from 4 to 6pm it is the only large user of the BP pages (DIS BP LSTATS on all object in the Buffer pool every 5 minutes)
There is an unique on a quite separated BP too. I forgot to take bufferpool stats on this index
We already urge the software company to rewrite the code to use TS queue (they choose this solution because sharing TS queue dis not existed in previous release of CICS ) , but it is another story.
Last friday, the table was very disorganized and until 4:55pm , the number of getpage (and sync IO) on this object was hundred millions, causing unavaibility of the application. there was almost no sequential reads.
Then after 4:55, suddenly no more getpage , and no more sync/IO , seq reads is still stable.
The number of transactions using this table did not decreased , in contrary, there were more transactions using it.
So my question is : what can happen that explain that the table is still disorganized , still use as usual , the workload didn't change but no more the disorganization effect ?
tHANK YOU for your valuable inputs and sharings.