As the HP 3000 was winding its way out of the HP product lineup, it gained a greater footprint. Storage capabilities grew with the rollout of Large Disk. The effort was undertaken because HP's disk module sizes were doubling in size approximately every two years: 4 GB to 9, 18, 36, 73, 146, and then 300 GB.
The disk project might have never seen its limited release without OpenMPE. The advocacy group that was formed after HP's exit announcement saw the same disk size trend. OpenMPE drove the initiative of "Support future large disks" in the Interex 2003 Systems Improvement Ballot.
Just two years later, Interex was dead. The directive from the 3000 community to HP labs lived onward, though. HP said its investigation found the need for more work to be done to support large disk configurations.
The MPE/iX 6.5 Large File enhancement allowed bigger Files. 6.5 also permitted more disk space in each MPE Group and Account. But several CI commands and utilities were limited in their ability to work with the resulting larger Groups and Accounts. All of these inputs were assessed during the Large Disk investigation and as many as possible were addressed by the Large Disk patches.
So what does Large Disk deliver? The patches provide the following enhancements for MPE/iX 7.5:
• Large Disk includes the ability to attach and use SYSGEN to configure any sized SCSI-2 compliant Disk. MPE/iX uses SCSI-2 protocol to connect to SE, HVD and LVD SCSI Disks as well as Fibre Channel over SCSI. The SCSI-2 standard allows for disks of up to 2 Terabytes. SCSI-3 disks may be larger but will only report up to 2 Terabytes of storage for SCSI-2 format inquiries.
• Large Disk includes the ability to initialize an MPE/iX Disk Volume of up to 512 Gigabytes on SCSI-2 compliant disks. SCSI-2 Disks that are larger than 512 GB are truncated at the 512 GB limit. No matter how big the disk, HP reported, the space beyond 512 GB will not be usable by the MPE/iX or any applications.
There are limits to how much Large Disk is available. And MPE/iX disk volume includes disk-resident OS data structures that use some disk space, so no more than 511 GB of user file space should be expected.
• Large Disk includes a number of opportunistic enhancements to MPE Command Interpreter commands and utility programs to 'smooth' user experience when dealing with large disks, large groups and large accounts. These commands and utilities are REPORT, :[ALT|LIST|NEW][GROUP|ACCT], FSCHECK, and DISCFREE.
HP strongly advises installing all of these patches at the same time using Patch/iX. The Large Disk Patches are:
• MPEMXX8(A) -- FSCHECK.MPEXL.TELESUP
• MPEMXU3(B) -- [ALT|LIST|NEW][ACCT|GROUP]
• MPEMXT3 -- SCSI Disk Driver Update
• MPEMXT4 -- SSM Optimization (>87 GB)
• MPEMXT7 -- DISCFREE.PUB.SYS
• MPEMXU3 -- REPORT
• MPEMXV2(A) -- CATALOG.PUB.SYS
• MPEMXW9(A) CIERR.PUB.SYS, CICATERR.PUB.SYS