I have a situation where we are writing to a Shark DASD from DB2. I know DB2 will start multiple write engines to write the data from the buffer pool. However all the writes will go to the same volume. My questions are about PAV. 1. The DASD controller will serialise writes to the same extent - as specified in the define extent CCW. What does DB2 specify for the extent? Is the the DASD extent or just the area it is writing to? If so what area is specified? I cannot find this documented anywhere. The many write engines will be trying to build the single table. 2. We may have many write engines started to the same DB2 table on a single volume. There may be many of these.What is the maximum number of PAVs that WLM will give it?
The reason for the question is to evaluate the benefit (if any) of running multiple JOBs which will all contribute to the data Db2 will write to the single tablespace (i.e. dataset). Terry Draper zSeries Performance Consultant ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
