-----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Frank Swarbrick Sent: Thursday, August 06, 2009 1:01 PM To: [email protected] Subject: Re: DASD: to share or not to share
>>> On 8/6/2009 at 11:47 AM, in message <45d79eacefba9b428e3d400e924d36b902557...@iwdubcormsg007.sci.local>, "Thompson, Steve" <[email protected]> wrote: > -----Original Message----- > From: IBM Mainframe Discussion List [mailto:[email protected]] On > Behalf Of Scott Rowe > Sent: Thursday, August 06, 2009 12:44 PM > To: [email protected] > Subject: Re: DASD: to share or not to share > > I think the real question here is: Why don't you have a SYSPLEX? There > is = > little to no cost involved, and many benefits. > <SNIPPAGE to a prior post by Steve Thompson> > If you set this up correctly, you will get Record Level Locking for VSAM > which will give you some benefits that you lost in moving from VSE. It > is something to think about, if you are heavily using VSAM with onlines > and batch. Can you explain this a bit more? I will admit to not even knowing how this works on VSE. <SNIPPAGE> Within DOS/VS-VSE the buffers are handled by DOS for an image. So you get to better share VSAM between Partitions (as in a VSE partition) than you can between z/OS Address Spaces. This allows, as I recall (it has been several years since I've done any VSE-VSAM work on a VSE system), more than one partition to have an ACB open to output to a file (share options that are NOT available on MVS if you compare your VSE IDCAMS against z/OS IDCAMS doc). With RLL (Record Level Locking), you can now have batch and onlines updating VSAM files at the same time. This goes a step beyond what VSE allowed, giving you certain performance boosts that were lost in going to z/OS where buffers are controlled within an address space as opposed to within an instance of VSE (image). Regards, Steve Thompson -- Opinions expressed by this poster may not reflect those of poster's employer -- ---------------------------------------------------------------------- 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
