midrange-l-request@xxxxxxxxxxxx wrote: > 9. RE: Disabling Qinter... (Follow up question) (jt) > >So, the order the subsystems are started is the key, afaik. Again, that may >NOT be how it used to work but that's my recollection, and it Certainly may >not even apply any more as the OS sure Has Changed over the decades. I've had a slightly different impression over the years that somewhat explains the unpredictability of which subsystem gets the device. It isn't exactly which subsystem starts first, although that certainly can affect the outcome. I've thought it's more accurate that it's which subsystem attempts to allocate the device first, regardless of which starts first. Think of two subsystems started in a CL program one after the other: ===> strsbs SBS1 ===> strsbs SBS2 The first STRSBS command will complete almost immediately, and the second command is executed. We then have two subsystems starting up at the (more or less) same time. If you watch them perhaps via WRKACTJOB, you'll see them both running through devices trying to allocate them. Now, imagine SBS1 has all workstations listed for allocation while SBS2 is only defined to allocate device ZZZZZZZZ, which was created only recently after a whole bunch of other devices already existed. Since SBS2 has only the single device in its table, it almost certainly will be able to get it allocated before SBS1 has the time to get around to it. So even though SBS2 "started" last, it wins. I also have thought that device names, or identifiers, aren't necessarily stored with the subsystem description in alphabetical order, but instead in perhaps a FIFO order tied to the date/time it was first defined to the subsystem description. So, if ZZZZZZZZ had been the very first device created and assigned, SBS1 might be much more likely to get it before SBS2 can. Beyond the possible orderings of device identifiers, the handling of errors on various devices during allocation can slow the process significantly for one or the other subsystem. This would also decrease predictability. If somebody really knows how it works, it might be instructive to the rest of us. Tom Liotta -- Tom Liotta The PowerTech Group, Inc. 19426 68th Avenue South Kent, WA 98032 Phone 253-872-7788 x313 Fax 253-872-7904 http://www.powertech.com __________________________________________________________________ Introducing the New Netscape Internet Service. Only $9.95 a month -- Sign up today at http://isp.netscape.com/register Netscape. Just the Net You Need. New! Netscape Toolbar for Internet Explorer Search from anywhere on the Web and block those annoying pop-ups. Download now at http://channels.netscape.com/ns/search/install.jsp
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