I understand that without PAV an ECKD volume cannot have have multiple I/O operations in progress and therefore the operating system (or is it the channel ?) may have to queue I/Os to a volume. I know that this applies to z/OS and I assume that it also applies to z/VM and linux, and may be a reason to avoid using very large ECXD volumes.
Does the same apply to a traditional channel-attached FBA volume (ie not FCP-over-SCSI) ?. For mini-disks on z/VM emulated FBA on SCSI, I assume that at the z/VM can issue several simultaneous SCSI IOs to the LUN but will each linux guest still limit itself to one I/O per mini-disk ?. Does the use of DIAG access to the mini-disk make any difference ? Keith ---------------------------------------------------------------------- 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 more information on Linux on System z, visit http://wiki.linuxvm.org/
