Hi, In our environment, we have a mix of emulated 3390-9 and 3390-54. When we have a need for small volumes (page, etc), we use 3390-9s and backfill them with rarely referenced files - documentation, etc. I tend to keep the system on 3390-9s (except SMPPTS!), as there was (once) a bit of a performance hit on the emulated 3390-54s. Not sure if that's still true. The physical drives are 650GB, and with the cache in front of them, I'm not sure it matters anymore. I'd be interested to hear opinions on this. Thanks! BobL
-----Original Message----- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf Of Skip Robinson Sent: Friday, February 22, 2013 1:40 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: Mod-9 vs. Mod-27 vs. mixed [ External ] In the interest of frugality, I asked my storage guys some time ago to allocate some tiny volumes for JES checkpoint and couple data sets. After a while, they complained that it was more trouble than it was worth because we mirror most volumes to the DR site. For every tiny source volume, they needed a corresponding tiny mirror volume. Periodic DASD refresh (aka upgrade) projects only added to the complexity. Pennies vs. pounds. . . JO.Skip Robinson Southern California Edison Company Electric Dragon Team Paddler SHARE MVS Program Co-Manager 626-302-7535 Office 323-715-0595 Mobile jo.skip.robin...@sce.com From: "Staller, Allan" <allan.stal...@kbmg.com> To: IBM-MAIN@LISTSERV.UA.EDU, Date: 02/22/2013 10:04 AM Subject: Re: Mod-9 vs. Mod-27 vs. mixed Sent by: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> Space wasted for "small volumes" e.g. XCF couple datasets. Just a talking point. With Hyper-PAV, etc. most of the other points are just "hot air". The convenience of not having to support multiple "geometries". <snip> A client with DS8000 DASD configured as a mix of 3390 Mod9 and Mod27s is considering a project to convert everything to Mod-27. Does anyone out there have some thoughts on the advantages or disadvantages of this? I'm not looking to start a religious discussion or other "dinotribe," so feel free to respond to me privately. I'm just interested in perspective and talking points, either way. </snip> ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN This e-mail transmission may contain information that is proprietary, privileged and/or confidential and is intended exclusively for the person(s) to whom it is addressed. Any use, copying, retention or disclosure by any person other than the intended recipient or the intended recipient's designees is strictly prohibited. If you are not the intended recipient or their designee, please notify the sender immediately by return e-mail and delete all copies. OppenheimerFunds may, at its sole discretion, monitor, review, retain and/or disclose the content of all email communications. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN