Hi, On Sat, Mar 23, 2013 at 11:11 AM, john s wolter <johnswol...@wolterworks.com> wrote: > > I've been using VirtualBox in Windows 7 on a Sony Vaio Duo Core /w 4 > gigabytes of RAM. VirtualBox's load times are okay but the execution of > MS-DOS & a particular character-display application program is usable very > but slow.
It's never going to be full speed nor perfect emulation. It's too tricky to emulate everything (esp. pmode). Anything to do with segmentation is probably lower priority (due to complexity and deprecation) than the bare minimum (686-ish pmode) that *nix and Windows require. > Understanding this issue is best approached by examining VirtualBox and > FreeDOS separately from the application. > > Is there a known good setup for VirtualBox and FreeDOS that demonstrates > good performance? I know I sound like a broken record, but having VT-X enabled (if possible, esp. nested page tables or whatever) is the only best setup I know of. > Inside this question is how to measure the performance of > VirtualBox and then DOS other than just by it feels okay. Probably best to try some (official or unofficial) benchmark, e.g. Dhrystone, doom -timedemo demo3 (for 1.9 shareware), or just timing some random cmdline program (runtime ..., esp. archiver or compressor) or DJGPP compile of something (redir -t gcc ...). I guess it depends on what you're trying to test (FPU, gfx, etc). > Second, what steps should be taken to walk through application performance > issues within FreeDOS? Is there a sequence that would narrow issues to > solutions? Not that I know of. You'd have to debug VirtualBox itself (or maybe it can optionally have a built-in debugger like some other emulators?? dunno ...). Most of the issues are x86 emulation, then BIOS, then peripherals (mouse, keyboard, CD, etc). ------------------------------------------------------------------------------ Everyone hates slow websites. So do we. Make your web apps faster with AppDynamics Download AppDynamics Lite for free today: http://p.sf.net/sfu/appdyn_d2d_mar _______________________________________________ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
