Thanks for all the answers guys. All the information is very appreciate. Rogério Soares
On Fri, Nov 6, 2009 at 6:30 PM, David Boyes <dbo...@sinenomine.net> wrote: > > I will need left to behind the ECKD, the storage's guys tell me that > > i > > need use LUN's now.. So, what kind of setup is more effective ? > > EDEVs will cause the least disruption in how you manage your VM system, and > IMHO, are far less confusing to set up and manage. There is a performance > hit from direct access, but the two methods can coexist if you need maximum > performance for a particular virtual machine. Your CP and other CMS volumes > will need to stay on EDEVs. > > > I have heard about lost I/O > > automatic > > balance if i use LUN directely, this is true ? > > It's not lost, but in dedicating the LUN to the virtual machine, you have > to tell that virtual machine how to do it instead of CP just dealing with > it. That's the nice part about EDEVs; CP continues to do that work for you. > > > Using edev lost more space with disk format then use lun direct? > > You lose 4 512 byte blocks for the IBM standard label on an EDEV. Minidisks > are a 1 to 1 match. > > > about > > performance, there is very difference ? > > At very high I/O rates, the difference is measurable (and will certainly be > worse than full-on FICON). But, if you have certain virtual machines that > are impacted, attach LUNs directly to those problem systems and leave the > rest on EDEVs. > > > Thanks for any tip! :) > > Use EDEVs for most systems. Deal with individual problem systems by > dedicating things if you need to. > > -- db > > ---------------------------------------------------------------------- > For LINUX-390 subscribe / signoff / archive access instructions, > send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or > visit > http://www.marist.edu/htbin/wlvindex?LINUX-390 > ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
