Issue 3: April 1987

• Applications software on the Cray X-MP/48
• Dataset Management and the M860

Applications software on the Cray X-MP/48

This is a progress report on applications software installed on and planned for the Cray X-MP/48 at the Joint Research Councils Supercomputer Unit (JRCSU) in the Atlas Centre.

If there is any other software you think should be installed on the X-MP/48 then please let us know.

Already installed are:

GHOST-80

A library of Fortran routines for graphical output. GHOST produces either GKS metafiles for plotting or viewing locally at RAL or TRANGRID metafiles for shipping across JANET for plotting on other machines running GHOST.

GINO-F 2.6 and 2.7C

A set of routines, written in ANSI standard Fortran, providing simple 2D and 3D graphics capabilities. Produces pseudo code output for storing a picture in a machine and device-independent file for subsequent retrieval. Output files can be transferred by FTP to other sites or viewed on a graphics terminal attached to CMS.

GINOGRAF

A complementary set of GINO routines for producing pie charts, graphs, bar charts and histograms.

GKS

The standard graphics system. Produces metafiles for printing on one of the Centre's hard-copy devices or for viewing on a graphics terminal attached to CMS.

GLIM 3.77

Generalised Linear Interactive Modelling is a statistical analysis program which allows the fitting of generalised linear models to data which can be scalars or vectors, numbers or strings of characters.

HARLIB

The Harwell library comprising about 200 mathematical and numerical analysis Fortran subroutines.

NAG LIBRARY MARK II

The Numerical Algorithms Group's Fortran subroutine library comprising over 500 mathematical and statistical routines. It has been adapted to make use of the vector capabilities of the Cray.

NAG GRAPHICAL SUPPLEMENT MARK 2

A Fortran subroutine library of high-level graphics routines which complements the NAG Library. The NAG Graphical Supplement can be used with GKS. GHOST-80 or GINO as the low-level graphics system.

SHELXS-86

A Fortran 77 program for the solution of crystal structures from diffraction data. It is accompanied by PATSEE for Paterson Interpretation.

XTAL 2.1

A package of portable programs for small-molecule and macromolecular crystallographic calculations. The package includes a Ratmac preprocessor which converts the XTAL source code into Fortran 77.

CCP-developed packages

A number of packages and programs developed under SERC Collaborative Computational Projects (CCP) have been installed. These include ATMOL, CAD-PAC and GAMESS.

Coming soon: ABAQUS

A general-purpose finite-element program designed for advanced engineering analysis applications, with special emphasis on non-linear problems.

GAUSSIAN86

This is a quantum chemistry package which allows the calculation of the structure of both stable molecules and molecular structures too unstable to isolate and study by conventional methods.

FELIB

A subroutine library of tools for Finite-Element analysis.

IMSL Library

An American equivalent of the NAG Library comprising over 500 Fortran subroutines for mathematical, statistical and general applications.

PROLOG

Cray's version of the non-procedural programming language based on the first-order predicate calculus. It uses several new techniques, including partial clause compilation, to achieve efficient execution on a Cray supercomputer.

SCIPORT

A portable Fortran emulation of Cray's SCILIB which is a library of scientific applications subprograms developed especially for the Cray supercomputer. SCIPORT allows program development on a range of other computers with production runs on the Cray requiring no changes to applications software.

SPICE

Simulation Program with Integrated Circuits Emphasis is a general-purpose simulation program for non-linear DC, non-linear transient and linear AC circuit analysis.

TSA

Time Series Analysis package which allows both frequency and time domain analyses of a series.

Tim Pett, Systems Group Leader

Dataset Management and the M860

Data management on the Atlas Centre mainframes uses a range of magnetic hardware with diverse properties.

The disks attached to the Atlas-10 and 3081 can hold about 30 Gbytes of data, and are divided about equally between VM/CMS and MVS. Those attached to the Cray for COS can hold about 14 Gbytes. These disks have access times of a few hundredths of a second and data transfer rates ranging from 1.2 Mb/sec for the slower VM and MVS disks to 10 Mb/sec for the Cray disks.

There is also a Masstor M860 magnetic cartridge device. The M860 contains about 630 cartridges, each with a capacity of about 170 Mbytes of data, that is 110 Gbytes in all. It takes about 10 seconds to load a cartridge into a read/write station and position it, and then the data transfer rate is up to 1 Mb/sec. MVS, CMS and COS all have direct access to the M860 device.

The three systems MVS, CMS and COS have essentially separate filestores, although there are many ways of transferring data between them. All systems attempt to keep the more recently used data on their own disks. Less recently used data is migrated from disks into the M860 storage device, from where it can be transparently recalled to disk when it is required. This migration considerably increases the effective online file storage space in a manner transparent to users and jobs. In addition, the systems keep extra backup copies of data offline on standard magnetic tape.

The operating systems use different software systems to manage this migration and retrieval, but they all eventually request cartridges to be mounted in the M860 for reading or writing, leading to a requirement for global scheduling of M860 functions.

For this reason, the M860 is controlled by a VM server virtual machine, which performs two main functions. Firstly, it maintains information for each cartridge such as in which cell it lives and by which operating system it is owned. Secondly, it receives requests to mount cartridges for reading and writing from the various operating systems and schedules these as hardware components become available. Once a cartridge has been mounted, the operating system that requested the mount can read and write at high speed via its direct connection to the M860.

The following table and notes are a summary of data management facilities and parameters at the Atlas Centre.

1. At present, about half of this is contained in the old CMS archive system, which will eventually be phased out, being replaced by ordinary minidisks. This figure includes much of the CMS 'system' data (S, Y disks, CMS/CP source etc), which the corresponding MVS figure does not.
2. In general, files should be spread across minidisks to keep the maximum minidisk size below 30Mb.
3. First figure is for UNIT = TRANS, second for UNIT = STORAGE.
4. Under review, filespace will probably eventually be rationed by flexible quantity limits like CMS.
5. Filespace is rationed by the quantity limits of the minidisk manager, and is automatically purged only when the owning username is deleted.
6. This is the total size of files actually existing at present.
7. CMS uses a fixed block structure, so the CMS figure is the data capacity at that block size. MVS uses variable block sizes, so the MVS figure is an estimate.
8. Minidisks are not removed from disk until the space is actually required, so this figure is more accurately a minimum period.
9. This figure varies between the systems because the way the space on a cartridge is split up affects the search time to locate the data.

David Rigby, Systems Group