From: Charles Sandmann Newsgroups: comp.os.msdos.djgpp Subject: Re: DPMI-Alloc with 192MB RAM - how ? Date: Thu, 22 Jul 1999 22:07:32 CDT Organization: Rice University, Houston, Texas Lines: 37 Message-ID: <3797dc74.sandmann@clio.rice.edu> References: <7n7si0$ae1$1 AT news DOT luth DOT se> NNTP-Posting-Host: clio.rice.edu X-NewsEditor: ED-1.5.9 To: djgpp AT delorie DOT com DJ-Gateway: from newsgroup comp.os.msdos.djgpp Reply-To: djgpp AT delorie DOT com > : No, it supports up to 256MB of physical and additional 256MB of paged-out > : memory, for a grand total of 512MB of vurtual memory. If this doesn't > : work for you, either you have an old version of CWSDPMI (before r4), or > : something is wrong in your setup, or some memory manager you install > : prevents CWSDPMI from giving you more. > > Hmm. My lastest box (the screaming 20MHz with 4MB of RAM) seems to > think differently: > DPMI memory available: 3414 Kb > DPMI swap space available: 129818 Kb Okay, I just found out my news server has been eating all posts for the last 6 months or so -- let me summarize! 1) To provide more than 128Mb virtual memory you need to use CWSPARAM to increase the max swap file size. This eats up DOS 640K memory - about 32 bytes for each 1 Mb maximum swap usage (for the bitmap). This would be an extra 4K of DOS memory to go from 128Mb virtual to 256Mb virtual. 2) To provide more than 64Mb physical memory, you need HIMEM.SYS from a Win 9x release or a commercial memory manager. The BIOS calls only support 64Mb max (best case) and only 16Mb max (worse case) - so this might be all you see with an empty config.sys. Adding EMM386 may decrease the amount of memory available, so if you need a lot of memory and use EMM386 (for UMBs?) use NOVCPI and/or NOEMS. 3) There is a BUG in r4 which prevents usage of more than 255Mb total virtual memory. If you have 128Mb or more of physical memory you need to run CWSPARAM to decrease your swap file size so the total available is less than 255Mb. If you don't - then you can't even use all the physical memory without page fault bugs! (Example: 120Mb max on a 128Mb machine). 4) There is a BUG in r4 which prevents usage of more than 128Mb physical memory (even worse, any physical address above the 128Mb mark!) 5) I have fixed the bugs in 3 & 4 in a beta WIP r5. The new release will support 2Gb total memory - I have personally tested 1.2Gb of total memory (1Gb physical, 200Mb virtual) on the WIP version. I'm busy at work and probably won't get it done for another month or two. 6) I'm considering low effort requests for r5.