Hi Ralf and Ira, > The problem is just to load everything and the kitchen sink by default, > regardless if needed or not. FDAPM is not necessary to run FreeDOS
The kernel has a built-in IDLEHALT option which you can activate in config sys and which already implements the core idea: To stop the CPU (or give away a time slice in case of virtual computers) at "obviously idle" moments. FDAPM itself has a few additional features such as displaying statistics about how idle DOS was or capturing more idle moments than a DOS kernel itself is aware of. > Beside that the last APM spec (v1.2) is now 20 years old and for at > least 19 years superseded by ACPI and I am not sure if FDAPM does... FDAPM only supports very few ACPI functions, notably powering off your computer for systems where the BIOS no longer supports APM and the old ACPI throttle where the mainboard freezes the clock for N out of each 8 (sometimes 16) time slices of e.g. 1s / 32k. Because ACPI, even in the oldest versions, is a complex description and programming language with a virtual machine and everything, the few things done with ACPI by FDAPM are based on "keyword spotting" in the ACPI code. In particular on newer systems, this often fails. However, implementing a full ACPI VM would make FDAPM really huge. Another FreeDOS tool which does things with less ancient computers is PCISLEEP, which checks which of your PCI (or AGP or PCIe) cards and devices support the easiest energy saving modes and offers to put them to sleep or wake them up. In case of graphics cards, this includes trying to re-boot the graphics BIOS. Again, implementing a full energy saving system would make the tools huge, because PCI also has "state loss" energy saving modes where you have to backup and restore all hardware settings after wake-up. Plus you want the devices to sleep and wake in a good order, e.g. bridges vs. disks. So in short, this is all interesting to look at (in particular, my PCISLEEP works great as minimalist LSPCI alternative for DOS), but if you want maximum battery life, use a big modern operating system with advanced drivers for the various components of your hardware. If you only want to avoid fast battery drain and lower fan noises, or want to keep your virtual PC / QEMU / virtualbox / whatever from hogging a complete CPU core, then the IDLEHALT option built into FreeDOS kernel, together with BIOS settings, already helps quite a bit and the other tools are for making the experience a bit nicer. Regards, Eric PS: If any of the tools does something stupid, by misunderstanding a too modern system, remember the ACPI emergency override: Press the power button for several seconds to force a power off (or on). Can be useful when you manage to switch off cooling at full speed, or when you get stuck in a sleep state without wake-up button/key. ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
