First some history. VM supported a form of PAV for paging back in 1984, back then development didn't have a problem supporting up to 4 addresses per page volume for the 3880-21. So this function should be doable.
PAV was added to z/os because disk sizes were getting larger, and the z/OS folks were rightfully concerned and thinking about the future, something that needs doing more on the VM side. The workloads running on linux are changing extremely fast. 3 years ago, it was small infrastructure, not a lot of I/O. 2 years ago, it was 31 bit WAS, ORACLE more I/O, but dbconnect leaving the I/O on z/os seemed very common. Now installations are starting to do real I/O with 64-bit apps. Who can predict i/o patterns of all these new applications that have never been analyzed before? I keep hearing it will take a long time for PAV to be added. so when we do have problems, then maybe 2 years later we'll get a fix? once we can show I/O queues? gee thanks. in the mean time, tell your z/os folks that vm does not support PAV, and you don't want their 3390-27, or even 3390-9.... >Date: Wed, 6 Apr 2005 13:31:08 -0500 >From: Marcy Cortes <[EMAIL PROTECTED]> >To: LINUX-390@VM.MARIST.EDU > >Do you have any mod 27's? I wonder if it is a potential problem >with the big disks but no one in the real world has tried them >because it is pretty darn hard to go back to a smaller size. > > >Marcy Cortes >WFS Enterprise Hosting Services - VM & Linux > >-----Original Message----- >From: Linux on 390 Port [mailto:[EMAIL PROTECTED] On Behalf Of Rich >Smrcina >Sent: Wednesday, April 06, 2005 11:33 >To: LINUX-390@VM.MARIST.EDU >Subject: Re: [LINUX-390] Latest on PAV's? > >I've been watching all day and no queuing so far. > >Alan Altmark wrote: >> On Tuesday, 04/05/2005 at 07:41 EST, Rich Smrcina <[EMAIL PROTECTED]> >> wrote: >> >>>Devil, >>> >>>Minidisks here. >> >> >> I did not mean to imply that no one uses mindisks and I certainly was not >> suggesting a poll! After all, "some of my best friends use minidisks!" >> :-) >> >> Of those using mindisks in production, I am curious to know if you are >> seeing queuing for the volumes during steady-state operations. Feel free >> to respond off-list if you prefer. >> >> Alan Altmark >> z/VM Development >> IBM Endicott "If you can't measure it, I'm Just NOT interested!"(tm) /************************************************************/ Barton Robinson - CBW Internet: [EMAIL PROTECTED] Velocity Software, Inc Mailing Address: 196-D Castro Street P.O. Box 390640 Mountain View, CA 94041 Mountain View, CA 94039-0640 VM Performance Hotline: 650-964-8867 Fax: 650-964-9012 Web Page: WWW.VELOCITY-SOFTWARE.COM /************************************************************/ ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
