swh@hpcupt1.HP.COM (Steve Harrold) (08/14/89)
Can HIMEM.SYS co-exist with VDISK.SYS? The HIMEM.SYS driver supplied with (I think) Windows/286 allows you to use the first 64KB of extended memory (less 16 bytes) as part of conventional memory so that you can effectively extend the 640KB boundary by 10%. A number of memory-hog applications are now available to make use of this "free" memory space. This is all well and good. BUT, if I use the VDISK.SYS driver to create a RAM-disk in the remaining space on my extended memory card, will I suffer any unhappy consequences? Will VDISK try to access the same memory space that HIMEM uses? In a nutshell, can HIMEM.SYS and VDISK.SYS co-exist in a 286 machine? -- --------------------- Steve Harrold swh@hpda.hp.com ...hplabs!hpda!swh HPG200/11 (408) 447-5580 ---------------------
baird@cod.NOSC.MIL (John M. Baird) (08/16/89)
From article <-286529991@hpcupt1.HP.COM>, by swh@hpcupt1.HP.COM (Steve Harrold): > Can HIMEM.SYS co-exist with VDISK.SYS? > In a nutshell, can HIMEM.SYS and VDISK.SYS co-exist in a 286 machine? If you have DOS 3.0 or later and the version of HIMEM.SYS that comes with Windows/286 (or 2.10), or 2.06 HIMEM.SYS direct from Microsoft (they give it away for free, SIMTEL20 has it), HIMEM.SYS and some RAM disk programs can co-exist. The one from Microsoft that comes with Windows (RAMDrive) certainly can. I don't know about VDISK.SYS or some of the popular third party RAM drivers. Appended is an excerpt from the README.TXT file for Windows/286 that gives some more information on the topic. If you configure VDISK so that it leaves 64KB for HIMEM, and install HIMEM first in CONFIG.SYS, chances are good it will work. John Baird, Naval Ocean Systems Center, San Diego, CA [with annotations in square brackets] ================================================================================ MICROSOFT WINDOWS/286 VERSION 2.1 ================================================================================ Using SMARTDrive [their cache disk driver] ---------------- Appendix C, "Speeding Up Windows with SMARTDrive" in the Windows User's Guide contains detailed instructions on installing the disk-caching program SMARTDrive provided with Windows 2.1. Using RAMDrive [their RAM disk driver] -------------- In general, SMARTDrive gives better overall performance than RAMDrive. One exception is output performance for frequently written files. We recommend that you use SMARTDrive; however, a new version of RAMDrive is included with Windows 2.1. Using HIMEM.SYS on 286 or 386 machines with extended memory ----------------------------------------------------------- On 286 or 386 machines with extended (NOT expanded) memory, it is possible to gain between 45Kb and 60Kb of additional conventional memory. To gain this memory, the driver, HIMEM.SYS, must be installed in your CONFIG.SYS file. [before anything that calls it, like RAMDrive or VDISK.] If HIMEM.SYS is installed and you do not have at least 64Kb of available extended memory, it is either because you don't have enough extended memory mapped to segment FFFE, or because SMARTDRV.SYS or RAMDRIVE.SYS have already allocated that memory. o Make sure that RAMDRIVE.SYS and/or SMARTDRV.SYS do not allocate all of your extended memory. At least 64Kb must be reserved for HIMEM.SYS. o If you have an EXPANDED memory card which you plan to use for HIMEM.SYS, you must configure the expanded memory hardware such that at least 64Kb of the memory on the card will be used as EXTENDED memory. ================================================================================ END OF README.TXT ================================================================================
ppa@hpldola.HP.COM (Paul P. Austgen) (08/19/89)
I have had problems with VDISK and the extended memory driver for a BOCARAM extended memory card. (The card doesn't work very well either, but that is another story). I used RAMDISK from Microsoft instead of VDISK, and everything seemed ok. You can't use VDISK with Windows anyway, so I think it is best to just plan on switching to RAMDISK, which seems to do the same thing.