Barbara, Yes it is a confusing subject. The MSR value was there at day one with PDSE. It had to set to 3ms whereas must cache was 6ms for 3390-3 or smaller as I recall. There was a bug that disabled this, but then it was returned.
We'll wait and see if some of those presentations match what is observed in the SMF records. You've sleeper program has already verified that you are getting directory caching when another address has the file open. That conflicts with the statement below. Ron > -----Original Message----- > From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of > Barbara Nitz > Sent: Friday, February 12, 2010 3:23 AM > To: [email protected] > Subject: Re: [IBM-MAIN] PDS vs. PDSE > > >PDSEs without a storage class are not cached in hiperspace: > >http://www.redbooks.ibm.com/abstracts/TIPS0567.html?Open > > > >("Ensure that SMS-managed PDSEs are associated with storage classes that > >have appropriate MSR settings. (Note that PDSE data sets shipped as part of > >the operating system are generally not SMS-managed, so they have no > storage > >class and therefore cannot be cached).") > > Well, that explains why the parm doesn't get us anything. It may also explain > why the directory cache is completely ineffective, especially as *that* is > also > set to the IBM default value, which is 2GB. > > What really galls me is that init&tuna reference doesn't even mention that! > And nonSMS managed PDSEs have been around a long time, too! So we are > supposed to just *know* when it's specified in IGDSMSxx, it doesn't apply to > PDSEs, only to *sms-managed* PDSEs. > > Good thing it's Friday. > Barbara > > ---------------------------------------------------------------------- > 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 ---------------------------------------------------------------------- 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
