Vol 1.3   Technical Information for IDMSâ Users    August 1992

IDMS for UNIX ?

CA-IDMS for UNIX is a complete dictionary-driven database management system with integrated 4GL tools, record level locking, scratch and queue management and OLTP processing . Features include SQL and native D ML, COBOL and ADS, TCP/IP protocol support , Mainframe /PC portability etc. etc.

As part of multiplatform portability, CA-IDMS and ADS are being made available on UNIX and VAX shortly. IDMS-UNIX will be based on the SQL engine of CA-DB (VAX and UNIX).

Many of the existing IDMS MF customers have been keen on having IDMS and ADS based OLTP solutions for UNIX. With IDMS/ADS on UNIX, portability of mainframe a pplications is extended.

Programming skills in IDMS and ADS are protected and customers can port applications either way, or develop applications on UNIX for standalone or later MF usage.

The data dictionary of IDMS UNIX is based on the IDD of IDMS-PC which The data dictionary of IDMS UNIX is based on the IDD of IDMS-PC which is functionally equivalent to IDD of mainframe IDMS. ADS and COBOL are compatible at source level to both PC and 370 platforms. UNIX support starts with HP-UX (9000), Motorola , NCR 3000, ATT SVR4,AIX, Etc.

PF Keys in ADSC

ADSC is the new dialog compiler which replaces ADSG. The task itself is running as an ADSA application. After intstalling Release 12, customers try ADSC etc and it works. But then they migrate a 10.2 dictionary and make it the default dictionar y or a secondary dictionary. Now the
real problem starts. PF keys won't work in ADSC, ADSA etc .

If we try to update TAT, we get a message DC451403 duplicate task code ... due to ADSA appearing in the old ÅACFØGEN as well as ÅTOOLTCF. So users have to first delete ÅACFØGEN in a migrated dictionary from TAT using the task ADSOTATU, before adding ÅTOOLTCF. This must be done for all migrated dictionaries.

Also make sure that we have the ÅTOOLTCF load module in the default load area. If the install dictionary SYSDICT is replaced by a 10.2 dictionary, we need to run DDDL job to have ÅTOOLTCF in the default dictionary. This must be done before upda ting TAT. It is not required to have ÅTOOLTCF load module in secondary dictionaries.

Release 12.0 Dictionaries

PIB Æ: CI76169 24 APR 1992

PROBLEM DESCRIPTION: Deficiency in CA-IDMS Rel 12.0 Conversion Notebook
HYPER: NO
PROBLEM RESOLUTION:
Conversion Note

It has come to our attention that there is a deficiency in the CA-IDMS Release 12.0 Conversion Notebook. If you attempt certain functions on a converted CA-IDMS Release 10.21 data dictionary you may receive errors (e.g. using the IDMSDMLC preprocesso r with certain protocols). To bring migrated Release 10.21 dictionaries up to Release 12.0 you should run the following jobsteps from JOB6 of the 12.0 installation, changing the dictionary name appropriately.

JOBSTEP Program Input
-------- -------- --------

APPLDEFS IDMSDDDL DLODDEFS
APPLPROT IDMSDDDL DLODPROT
TCFBTAT  ADSOBTAT inline
APPLADSR IDMSDDDL ADSRECDS
APPLEVBF IDMSDDDL RHDCEVBF*
	IDMSDDDL DLODAIDN

The last update executes IDMSDDDL with source member DLODAIDN. This was
not in the ESP9111 install job stream. You should copy any of the DDDL jobs and use the specified member as input. (*RHDCEVBF optional in secondary dictionaries. - Ed.).

Watch out for 1491

Release 12.0 provides complete upward compatibility for existing
databases and applications. No conversion is needed. ADS dialog load
modules from 10.2 can be used without recompilation.

If you are trying to run an existing 10.2 ADSO application without any
change, the most common error you may encounter is 1491. The reason is
that system is unable to resolve the database page range.

Example:
The following process try to access the EMPSS01 database.

*+ PROCESS NAME IS PDLG1-RP1
*+ USED BY PROGRAM DTVG1
*+ MODULE SOURCE FOLLOWS
*+ MOVE 1000 TO EMP-ID-0415.
*+ OBTAIN CALC EMPLOYEE.
*+ DISPLAY TEXT 'HOW ABOUT THAT'.

The above gave at execution time:
DC173001 APPLICATION
ABORTED. SUBSCHEMA BIND FAILED; STATUS=1491
-->OBTAIN CALC EMPLOYEE.

In the LOG (OLP or BCF print LOG), you may see a better message.
DB347006 V24 T369 EMPSS01 subschema requires a DBNAME to do bind run
unit

That's the reason. In 10.2 this would have worked since the subschema
contained the page-range and the system searches the DMCL to locate the
AREA matching the pages. But in release 12.0 there is no page
information in subschema. DBNAME is always req uired to resolve the page
range. DBNAME must be available at run time, either explicitly or
implicitly.

There are various ways to make DBNAME available at run time.
We look at 4 different alternatives.
1. Within process code

MOVE 'SCEMP' to DB-NAME.
MOVE 1234 to EMP-ID-0415.
OBTAIN CALC EMPLOYEE.

It is enough to have DB-NAME established in premap process of the
highest level dialog in application thread.

2. Before starting the application set the DBNAME using DCUF command.

DCUF SET DBNAME=SCEMP
ADS task-code

3. Give the DBNAME when you give the task code.

ADS task-code DBNAME=SCEMP
(End users will not like this!)
4. In the DBNAME table, give a default DBNAME for existing 10.2
subschema.

DBNAME *DEFAULT MATCH ON SUBSCHEMA IS OPTIONAL
SUBSCHEMA EMPSS?? MAPS TO EMPSS?? USING DBNAME SCEMP

DBNAME SCEMP MATCH ON SUB OPTIONAL
INCLUDE SEGMENT SCEMP

This probably is the best method for existing applications. No source
change in the dialogs are required. No extra housekeeping in the
existing applications are required either.
DBTABLE maintenance is completely transparent to the application
programs. Application can be executed exactly like the way you did in
10.2.

Apart from the above options many customers have 'home-made' solutions
with some driver programs in ADS or/and ASSEMBLER to do automatic
setting of DBNAMEs etc.
In batch DBNAME is given under a new DD card 'SYSIDMS'.

//SYSIDMS DD *
DBNAME=SCEMP
DICTNAME=SCDICT
DMCL=R120DMCL
/*
Ref: IDMS DBA Guide Release 12.0 Release 12.0 Conversion Notebook
Navigational DML Programming .

Benchmarking ADS/OnLine and IDMS/DC

In recent years there have been many commercial benchmarks on various database systems. Most of these benchmarks were aimed at convincing the users that the respective product is good enough for today's OLTP applications. Such commercial claims wer e never needed in the case of IDMS database. Ability of IDMS to give OLTP performance in DC, UCF or native CICS environments was never in question. When ADS was available in the eighties, it was the obvious choice for online applications. Thus we se e many customers running >1 million trs/day using 99% ADSO.

Eventhough everyone accepted the ease of use of ADS/O, a few wondered whether it could outperform 3GLs in terms of actual CPU usage. Note that enhancements were made to ADS in Release 10.21 and later so that most of the arithmetic operations generate executable 370 assembler code.

The following benchmark was done at an MVS site in Belgium at the ¦interest and full participation of the customer. At the client site, we ¦compared the CPU usage, database being loaded in buffers etc. for 3 ¦types of online transactions (small, med ium, large). Summary of results ¦follows:

Another benchmark at a VSE site showed that its CICS was eating up 50% of CPU dedicated to the VSE machine only to handle terminal I/Os. Replacing UCFCICS with IDMS-DC reduced this CPU consumption immediately. Further analysis of reports by CA-IDMS/P erformance Monitor, CA-JARS/DOS and CA-JARS/CICS revealed a 25% overhead in elapsed time in CICS partition.

Conclusion: Using IDMS-DC, you spare 26 percent CPU TIME compared to UCFCICS for an ADS application. PL1 application in CICS with IDMS database uses 22 percent more CPU than a clean ADS-DC. Even ADS-UCFCICS uses only 4 percent CPU more than PLI, in spite of the CICS overhead. This is indeed very good figures for a 4GL. Customers may note that a normal ADS-DC application can be executed from a CICS as well as IDMS/DC terminal without any source change at the same time.

Also we see that response time is adversely affected by elapsed time (in our case in CICS region). Isolation of IDMS-DB/DC from other regions is best for performance and operation department flexibility. DC allows us to dedicate an extra VTAM line for DBA activity. And the COMPACT option on the DC line reduces line traffic by 40%.

Big box not needed!

According to Computerworld (June 22, 1992 page 56), Hughes Aircraft Co. has downsized their IDMS application from a 4381 to a multiuser PC. Byn not using mainframe, the company saves more than $60,000 a month , whilen the PC system costs less than $2,0 00 per month. According to a spokesman from Hughes "We'are not losing anything in response time, there are no access problems, and the disk backup is user friendly, so I think users like IDMS-PC even more (than the mainframe version).

IDMS/PC 2.4 has support for extended memory on PC. This means that large dialogs of the order of 100K can be compiled and run on PC.
IDMS/LAN can support upto 64 users with full journalling and rollback capabilities. Unlike conventional 'file-servers', IDMS/PC does not send the whole file across the LAN. With record-level locking in IDMS/DB/PC, a minimum of information is transmi tted across the network, thereby making high transactions possible.

Today it is possible to have very large systems on PC. Customers are testing databases with 300+ record types in a single schema. Note that
this figure is considered 'very large' even for mainframe. CA's own this figure is considered 'very large' even for mainframe. CA's own Human resource System (CA-HRS) has been successfully 'downsized' to IDMS/PC.

Cooperative processing, SQL support (Release 12.0 compatibility) etc. are some of the features to watch for.

IDMS R12 9206 released

- a step closer to GA
Release 12.0 9206 released in Maintenance tape has been Westwood. Customers who have installed ESP tape 9111 can upgrade to 9206 using SMPnote that the . System programmers may new SVC is not compatible with the old oneupgrade proce . Else the SMP ss can be completed within half a day400+ . Release 12.0 is installed at sites worldwide now.

This tape contains all published APARS and important additions to ADS/O product linelatest CCI . Also it contains the driver for CA-Qbyx from PC-Windows.

A simple IDD tip

Users may note that IDD and DDDL compilers are just like any other database jobsstatements . Using COMMIT within IDD can free up locking resources in the systemespecially . This is relevant if you are running a long DDDL batch jobrunn ing . Also while heavy report jobs using IDD compilersretrieval , it is worth signing on in mode as 'SIGN USER XYZ PASSWORD ABC USAGE IS RETRIEVAL FOR ALL'.

Gøteborg Oktober 92

Scandinavian IDMS Userwill be 's Meeting held in Gothenburg on 29/30 October at Hotel Gothia. Detailed agenda being sent from IUA directly.

IMC - Jan 93 San Diego

CA-IDMS, Applications and Datacom World Conference

The Human Touch !

" There is no programming language, there is, no tool, there is no method that can magically replace the basic human creativity that is necessary to successfully design, implement and deploy a complex software system."
- Grady Booch, 91-92 author of Object-Oriented Design with ApplicationsPublishing , Benjamin-Cummings Co. Menlo Park, CA.