Last week, IBM announced the DPPX/370 operating system to enable users of the moribund 8100 distributed processor to move some of their applications over to the 9370 (CI No 890). Unusually too, IBM has rushed the thing out – its previous word on the subject had promised the thing only for the middle of 1989, which suggests that attrition of the 8100 base to machines from competing manufacturers had started to become intolerable. And all the signs are that the reception for the new operating system will be lukewarm – we publish the views of a few UK 8100 users alongside, and they are far from enthusiastic. There are several 8100 features missing from the first release, but this may be in part a reflection of the rush in which IBM has got it out, and some may well be added in future releases of the operating system. DPPX/370 runs native on the 9370 – and at present is offered only on the 9370: there is no word about supporting it on the 4381. No doubt it will also run as a guest under VM on the 9370, although that is unlikely to be a very interesting option for most users, and is not mentioned in the announcement. One of the first issues that is going to concern any 8100 users considering a move to the new DPPX/370 is the performance they are likely to get – and the news is not good. IBM says that any user hitting the performance ceiling on the top-end 8150B is going to have to go straight to the biggest 9370 currently on offer, the 9377/90, to get any improvement in performance. Using the company’s Internal Throughput Rate Ratio, the Model 90 comes out at twice the performance of the 8150B, the Model 60 is equivalent to the 8150B, while the Model 40 and the Model 20 each offer the same performance – 35% that of the 8150B. As reported, the only DPPX languages supported under DPPX/370 are VS Cobol II release 2 and CSP/AD – Cross System Product/Applications Development, either of which can be used on an MVS host for development of DPPX applications – but it sounds as if existing 8100 Cobol applications need to be recompiled. But if you want to continue to use your SDLC loop terminals, why you’re stuck with retaining at least one 8100 to manage them – the loop is not supported on the 9370. DPPX/370 is also limited in the 9370 features it can support: block multiplexor channels can be used only to connect the 3174 and 3274 terminal controllers and the Telex 1589 tape subsystem. The operating system does not support the 9370’s asynchronous adaptor; the IEEE 802.3 – Ethernet local area network controller; or binary synchronous communications. Otherwise, in general, the other features of the 9370 are supported. Telex tape Minimum requirement for DPPX/370 is 4Mb of memory, one disk drive – either 9332 or 9335, console and IBM 9347 or Telex 1589 tape drive to load DPPX/370. On the upside, there are a few pluses for users who convert: DPPX/370 supports the Token Ring local area network, supports Peer Data Transfer to other DPPX/370 systems – but apparently not to DPPX/SP on 8100s, although these can otherwise be mixed and matched with 9370s in a network. It also comes with a new System Configuration Manager and Multi volume User Catalogues. X25 support is provided. The applications distribution facilities of the old Distributed Systems Executive are now handled by NetView Distribution Manager. As reported, DPPX/370 is due to be available in December this year at a one-time UKP22,878 to UKP40,036 according to the size of the 9370 on which it is to run, or at UKP1,906 a month for all models of the 9370.
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