> -----Original Message----- > From: Alex Tough [mailto:[EMAIL PROTECTED] > Sent: Monday, November 12, 2007 7:33 AM > To: IBM-MAIN@BAMA.UA.EDU > Subject: Re: Performance comparison: Hiperbatch, BLSR, SMB? > > Peter > Apologies if this has already been answered, but the way for a job to opt > out of using Hiperbatch is to ask your RACF Security Admin to update the > DLF DATA segment for a particular dataset and remove that job or jobs > (using a wildcard) from the list of jobs that are allowed to access the > DLF object. I struggle to understand how BLSR can give better performance > than HB if all other system resources are equal (same WLM Service Class, > similar level of CPU contention). My understanding of BLSR is that it will > buffer parts (in Control Intervals) of your VSAM cluster into memory. If > you have all or most of the cluster allocated to a DLF data object, why > would BLSR be faster ? You say that you don't have access to SMF data, but > do you have access to RMF or Omegamon/Epilog to indicate what is causing > performance degradation ?
As to RMF access, I don't think so, but I've also not gone looking for it yet. Ditto for Omegamon/Epilog, but I can ask about it. I have officially asked the performance gurus here to look at these jobs and tell me what we can do to improve the performance. It's very hard for me to test different HB scenarios because HB is so strictly controlled by security methods and I have no authorization to use it. I do understand that BLSR may not help in this scenario, but having tested with SMB (without HB) and noted 50% savings in counted I/O's for that KSDS, I thought SMB would be a "good thing" to use. However, it apparently conflicted with HB and made the performance several times as bad as HB alone when we tried it out in the QA environment with HB active. Hence my research and questions here. Peter This message and any attachments are intended only for the use of the addressee and may contain information that is privileged and confidential. If the reader of the message is not the intended recipient or an authorized representative of the intended recipient, you are hereby notified that any dissemination of this communication is strictly prohibited. If you have received this communication in error, please notify us immediately by e-mail and delete the message and any attachments from your system. ---------------------------------------------------------------------- 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
