Tell the users to code REGION=150GB,ADDRSPC=REAL. They can run in a V=R region with 150GB of real storage, so they won't need to do any paging, thus eliminating the need for the 150GB of paging space. They will probably discover this option on their own and ask you for it if you don't suggest it first.
Or they could write their own sort, get their own virtual storage (150GB above the bar), then pagefix all that storagte, and thus not have to worry about paging. I am looking forward to hearing the results of their bubble sort. <<g>> Or they could ask the vendor of the sort product they plan to use for some ideas on how to accomplish their goal. Perhaps some Googling for sort techniques and/or performance pitfalls might help them, too. Is there a SORT-MAIN forum? Bill Fairchild Rocket Software -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Mike Schwab Sent: Wednesday, March 23, 2011 12:09 AM To: [email protected] Subject: Re: Region size Yes I did. I even suggested they do a VTAPE sort because our VTAPE device is 4X faster than our ESS 800s and ESS F20s. On Tue, Mar 22, 2011 at 9:40 PM, Joel C. Ewing <[email protected]> wrote: > I suppose you have at least tried to explain to those users that if > they actually tell a sort program it can use 150 GiB more storage than > the real storage on the machine that not only will they NOT get a fast > sort, but they will get an incredibly slow and expensive one because > of paging delays and paging overhead - and everything else running on > the machine for the long time it will take this to run will also see > response go to the dogs. They might not care about the latter, but > some other users of the system with more clout might. > > A decent sort utility that is given a realistic amount of virtual > storage that can be kept in its working set in real storage, and which > knows that the bulk of its temporary storage is on slower external > devices can optimize circles around the abuse of the paging system these > users are requesting. > > If the users can't understand that argument, you can probably expect > them to also write their own sort program and use a bubble sort - and > be surprised when it takes several years to run with that volume of > data! The task of sorting 150 GiB of data shouldn't be delegated to > neophytes that don't understand that resources have limits and that > there are good reasons why some techniques are deprecated. > J. C. Ewing > > > On 03/22/2011 03:41 PM, Mike Schwab wrote: >> >> I have some users who requested 150GB of Paging packs so they could >> do an in core reorg of multiple M9 volume DB2 databases, because that >> was the fastest way. I told them that was too much and they needed >> to specify sort work statements. They resisted and the request is >> pending. >> > >> On Tue, Mar 22, 2011 at 3:21 PM, Mark Pace<[email protected]> wrote: >>> >>> I assume that since it used 1792MB it has to be from above the line. >>> >>> There is not a dump. The program ends nicely with an error message, >>> not an IBM message, that it is out of memory. >>> >>> It's batch utility to massage SMF data and was not written inhouse. >>> The SE is talking with them now. There suggestion was to process >>> less data. :-D >>> >>> The LPAR is 4GB and I really don't know how much is to much. >>> >>> I don't have a default region size, that I know of. I allow the use >>> of REGION=0M and don't have any exit to limit that size. > > > -- > Joel C. Ewing, Fort Smith, AR [email protected] > Bentonville, AR [email protected] > > ---------------------------------------------------------------------- > 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 > -- Mike A Schwab, Springfield IL USA Where do Forest Rangers go to get away from it all? ---------------------------------------------------------------------- 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
