Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!wasatch!utah-gr!uplherc!sp7040!obie!wes From: wes@obie.UUCP (Barnacle Wes) Newsgroups: comp.unix.microport Subject: Re: Bell Tech W.G.E. use with "sissy" unix Summary: A couple of questions about the WGE/Blit... Message-ID: <224@obie.UUCP> Date: 11 Oct 88 05:37:29 GMT References: <438@l5comp.UUCP> <283@belltec.UUCP> Organization: the Well of Souls Lines: 33 In article <283@belltec.UUCP>, dar@belltec.UUCP (Dimitri Rotow) writes: | The cache problem is common to almost all intelligent boards (multiport, etc) | in use on AT bus machines. It's a special problem with display adaptors | with large display memory spaces because performance requirements force you | to map the card's memory somewhere into the AT map. Traditionally, one | chooses the upper part of AT memory under the (fair) assumption that it is | not populated with a full 16MB of RAM. | | The problem is that most cache equipped '386 boxes are designed by DOS houses | and have caches that are only turned off in the 640 to 1024K area used by | common DOS boards. The sensible thing to do (in a box designed for UNIX use | as well as DOS) is to have some means of disabling the cache for accesses | within a given range or above a given address. Many of the higher performance | '386 cache boxes now have that capability. Other companies (for example Dell) | will send you a special PAL that enables cache for a range less than the full | 16 MB address space. A couple of questions about the WGE/Blit card: Do you know if the cache on the Everex Step models or the ALR FlexCache models can be disabled above 14 Meg to work with the WGE? Users with an eye on performance will want to know this. How much real memory is needed (when using the current X10R4 code) to keep the system from paging like mad. I.e., the system should be able to run a couple of csh's or vi's without paging during program execution. -- {hpda, uwmcsd1}!sp7040!obie!wes "How do you make the boat go when there's no wind?" -- Me --