       $                               Compaq   Software Product  Description   C ___________________________________________________________________   ? PRODUCT NAME:  Compaq DECram for OpenVMS Alpha Version 3.1, and ! OpenVMS Alpha and VAX Version 2.3  SPD 34.26.10   DESCRIPTION   D Compaq DECram for OpenVMS Version 3.1 supports the OpenVMS for Alpha	 platform.   C Compaq DECram for OpenVMS Version 2.3 supports both the OpenVMS for $ Alpha and OpenVMS for VAX platforms.  D DECram for OpenVMS is a disk device driver that improves I/O perfor-N mance by allowing an OpenVMS system manager to create pseudo disks (RAMdisks),E which reside in main memory. Frequently accessed data can be accessed H much faster from a DECram device than from a physical disk device. TheseG RAMdisks can be accessed through the file system just as physical disks H are accessed, requiring no change to the application or the system soft- ware.   E Because main memory is allocated for a DECram device, extra memory is G generally required. The OpenVMS system manager can designate the amount C of memory dedicated to the DECram device(s) and the files that will  be stored on it.  C The main benefits of DECram for OpenVMS Version 3.1 are significant D performance enhancements for users running OpenVMS Alpha Version 7.3H and higher. In Version 3.1, DECram's capability is extended to use Open-E VMS Galaxy shared memory to create a VMS shared memory disk. This al- D lows users to take advantage of OpenVMS Galaxy shared memory without+ modifications to any of their applications.   C                                                            May 2002        E With DECram for OpenVMS Version 3.1, the limit on DECram disk size is E 4,294,967,296 blocks on OpenVMS Alpha systems running OpenVMS Version D 7.2-1H1 or higher. With DECram Version 2.3, the maximum disk size onE an OpenVMS Alpha system is limited to 67,108,864 blocks, and the max- E imum disk size on an OpenVMS VAX system is limited to 524,280 blocks. H It is possible to create logically contiguous devices greater than theseE limits by creating multiple DECram devices and binding them together.    Cluster Environment   E DECram Version 3.1 is fully compatible with DECram Version 2.3. There D can be any combination of these two versions of DECram in a VMSclus- ter.  C DECram Version 3.1 will run only on OpenVMS Alpha systems; however, F the RAMdisk can be accessed by OpenVMS VAX systems in an OpenVMS Clus- ter system.   < DECram Version 3.1 will run in the following configurations:  F o  AlphaServer systems with OpenVMS Galaxy configured with one or more,    instances as nodes in an OpenVMS Cluster.  $ o  Standalone OpenVMS Alpha systems.  D o  OpenVMS Cluster systems consisting of all Alphas or a combination    of Alpha and VAX systems.  D DECram Version 3.1 can be installed over a previously installed copyC of DECram Version 2.3, on Alpha systems only. If DECram Version 3.1 F is removed for any reason, DECram Version 2.3 is automatically removedC as well. If you want to continue to run DECram Version 2.3, it must  be reinstalled.   E If this is an initial installation of DECram Version 3.1, using Open- E VMS Version 7.2-1H1 or higher on an Alpha-based system in a clustered G environment, and all nodes that will be using DECram have a common sys- H tem disk, then only one installation of the DECram software on the clus-C ter is required. However, for each node in the cluster that will be E using the DECram product, a license key must be installed. If you are   "                                  2       C installing DECram in a cluster, be sure there is only one installa-  tion active at any given time.  D If this is an initial installation of DECram Version 3.1 using Open-E VMS Version 7.2-1H1 or higher in a clustered environment and there is H no common system disk, the DECram Version 3.1 software must be installedC on each node of the cluster where you want to create a DECram disk.   D If this is an upgrade of a clustered environment from DECram VersionF 2.3 to DECram Version 3.1, the DECram Version 3.1 software must be in-E stalled on all nodes in the cluster where you want to create a DECram  disk.   F Installation of DECram versions prior to DECram Version 3.1 on a clus-C tered system requires installation of the DECram software and a li- 8 cense key for all nodes that are members of the cluster.  E DECram Version 3.1 is fully supported when installed on any valid and . licensed standalone or clustered Alpha system.  E DECram Version 2.3 is fully supported when installed on any valid and E licensed standalone Alpha or VAX system, or any clustered VAX system.   C A minimum of DECram Version 2.3 is required for any OpenVMS Cluster - systems running any version of OpenVMS Alpha.   E DECram for OpenVMS Version 3.1 supports operation in an Adaptive Par- I titioned Multi-Processing (APMP) environment, also known as Compaq Galaxy F Software Architecture on OpenVMS. Previous versions of DECram must notE be used if RAM disks are being served, or served and shadowed, across F nodes within a cluster, or if DECram is being used in an Adaptive Par-# titioned Multi-Processing instance.   F Multiple DECram devices can be members of a Volume Shadowing for Open-I VMS shadow set and can be served by mass storage control protocol (MSCP). F There are no special hardware requirements to install DECram for Open- VMS.      "                                  3       G In DECram Version 3.1, Volume Shadowing for OpenVMS will support shadow E sets composed of DECram devices and other disk class devices. Removal D of the last non DECram device will cause the shadow set virtual unitC to abort and become unavailable. Please refer to the Volume Shadow- D ing for OpenVMS Software Product Description (SPD 27.29.xx) for more information.   User Interface  E With DECram Version 3.1, you can use the new DECram command interface C or continue using the same familiar commands from SYSMAN for creat- - ing, initializing, and mounting DECram disks.   F With DECram Version 3.1, the disk is configured using the DECRAM> userC interface to create and format the Random Access Memory (RAM) disk. E The INITIALIZE command is then used to write the OpenVMS cluster file  system to the RAM disk.   E With DECram Version 2.3, the user interface to a DECram device is the ! same as other disk class devices.    Management Interface  F A DECram device is managed by the same tools as any other OpenVMS diskG device. For example, the INITIALIZE, MOUNT, and DIRECTORY commands will F work the same on both hard disk and DECram devices. However, the stan-> dard utilities are used differently to set up a DECram device.   System Analysis   D Before creating a DECram device, the OpenVMS system manager must de-C termine its size. Each disk block allocated to a DECram device will G mean one less disk block of available memory. The system manager should G also assess the need for multiple DECram units. See Restrictions listed  below.   System Generation   E When adding a DECram device, the OpenVMS system manager must reassess E the values for the SYSGEN parameters that control paging and swapping 	 behavior.   "                                  4        Restrictions  < DECram for OpenVMS currently has the following restrictions:  C o  Data in a DECram device is volatile unless shadowed with a phys- 
    ical disk.   : o  DECram Version 3.1 cannot be installed on a VAX system.  D o  In DECram Version 3.1, the maximum size of a single DECram deviceF    on OpenVMS Alpha systems running OpenVMS V7.2-1H1 or higher is 2048    Gigabytes (GB).  D o  In DECram Version 2.3, a single DECram device size on OpenVMS Al-E    pha systems running OpenVMS Version 7.1 or higher is limited to 32     GB.  D o  In DECram Version 2.3, a single DECram device size on OpenVMS VAXL    systems running OpenVMS Version 6.2 or higher is limited to 256 Megabytes    (MB).  E Note: For disk volumes larger than 256 MB on VAX or 2048 GB on Alpha, C multiple DECram disk devices can be created and bound into a volume  set.  E DECram for OpenVMS is not designed to support long-term data storage. E If a system or hardware failure occurs, data stored in the DECram de- C vice is lost and must be recreated. This restriction does not apply F if the device is shadowed to a real physical device, using a supported$ version of OpenVMS Volume Shadowing.   HARDWARE REQUIREMENTS   D Processor and hardware configurations must conform to specificationsF in the OpenVMS Operating System Software for VAX and Alpha Product De-C scription (SPD 25.01.xx), or the appropriate operating system docu-  mentation set.      "                                  5        SOFTWARE REQUIREMENTS   E DECram for OpenVMS Version 3.1 supports OpenVMS Alpha Version 7.2-1H1 
 or higher.  C DECram for OpenVMS Version 2.3 supports OpenVMS Alpha Versions 7.1, C 7.2, and 7.3. A minimum of DECram Version 2.3 or higher is required D for any OpenVMS Cluster systems running any version of OpenVMS Alpha or VAX.   J DECram for OpenVMS Version 2.3 supports OpenVMS VAX Version 6.2 or higher.   ORDERING INFORMATION   OpenVMS for VAX    Software Licenses: QL-GJ9A*-** Software Media: QA-YL48A-H8 & Software Product Services: QT-GJ9A*-**  D DECram for OpenVMS Version 2.3 (for VAX) is distributed on the Open-C VMS VAX Software Product Library Distribution CD-ROMs (order number 
 QA-YL48A-H8).   8 DECram is no longer available on TK50 and magtape media.   OpenVMS for Alpha    Software Licenses: QL-MV3A*-** Software Media: QA-03XAA-H8 & Software Product Services: QT-MV3A*-**  F DECram for OpenVMS Version 3.1 (for Alpha) is distributed on the Open-C VMS Alpha Software Product Library Distribution CD-ROMs (order num-  ber QA-03XAA-H8).   F DECram for OpenVMS Version 2.3 (for Alpha) is distributed on the Open-C VMS Alpha Software Product Library Distribution CD-ROMs (order num-  ber QA-03XAA-H8).   "                                  6       F *  Denotes variant fields. For additional information on available li-D    censes, services, and media, refer to the appropriate price book.  E DECram for OpenVMS documentation is available in text, PostScript[R],  HTML, and PDF formats.   SOFTWARE LICENSING  C This software is furnished under the licensing provisions of Compaq E Computer Corporation's Standard Terms and Conditions. For more infor- D mation about Compaq's licensing terms and policies, contact your lo- cal Compaq office.  # License Management Facility Support   C This layered product supports the OpenVMS License Management Facil-  ity.  E License units for this product are allocated on a CPU-capacity basis.   E For more information on the License Management Facility, refer to the D OpenVMS Operating System for VAX and Alpha Software Product Descrip-C tion (SPD 25.01.xx), or the appropriate operating system documenta- 	 tion set.    SOFTWARE PRODUCT SERVICES   D A variety of service options are available from Compaq. For more in-, formation, contact your local Compaq office.   SOFTWARE WARRANTY   F This software is provided by Compaq with a 90 day conformance warrantyF in accordance with the Compaq warranty terms applicable to the license	 purchase.           "                                  7         ? [TM] Compaq, the Compaq logo, Alpha, OpenVMS, VAX, VMS, and the @      DIGITAL logo are trademarks of Compaq Information Technolo-9      gies Group, L.P. in the U.S. and/or other countries.   :          2002 Compaq Information Technologies Group, L.P.                                                                    "                                  8