On 3/19/18, 2:16 PM, "IBM Mainframe Discussion List on behalf of Paul Gilmartin" <[email protected] on behalf of [email protected]> wrote: > I suspect there is no longer economic justification for a specialized thin > client. X11 > servers are available very cheaply on almost any desktop system nowadays. > (Raspberry Pi?)
Relatively new development. Until Linux was fairly widely available, X11 on the desktop was pretty much restricted to Unix-based workstation hardware (with a few exceptions). The increase in network bandwidth, the ubiquity of Ethernet, and the processing power on the desktop are also big factors. > And long ago it struck me as absurd that ISPGUI relied on an idiosyncratic > "agent" on > every supported display platform. Operating as an X11 client with a > user-supplied > server would have made more sense. I think the argument at the time was that X11 was not prevalent on desktop systems at the time, took a large amount of processing power, and while X servers for Windows and friends did exist, they were extremely expensive and clunky to get a supported one (IIRC, Hummingbird, which had a decent Windows X server, was about $400/copy at that time). There weren't any free alternatives. Network latency was also a major issue -- at the time, 10 megabit shared Ethernet was still rare (at least inside IBM, anyway) and they went with what they knew. Cynically speaking, the ISPGUI approach also stopped non-IBM code from exploiting it since the app-> gui primitives were IBM-specific and not publically documented. On the old systems (when the top of the line 3090 was < 50 MIPS), the VM GUI client and the later ISPF GUI were much more responsive that the X environment due to offloading part of the client GUI rendering processing onto the client workstation, and required a lot less round trips between client and server which helped with the latency issue. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
