On Wednesday 25 October 2006 11:01 am, Paul Brook wrote: > > Oh, c'mon, Rob! I really didn't want to ask Paul Brook that, but > > sure you'll fix my cluelessness right here, right now - tell me, tell me, > > why Linux has dynamic-loadable modules support, which clueless passers-by > > like me call "plugins"? It must be closed-source diversion, no? > > Linux has genuine reasons for wanting modules. > Kernel size is important because (a) it has to be loaded by the bootloader, > often from a small, slow device (eg. floppy, flash or network). > (b) The whole kernel is permanently locked into ram. It you've ever tried to > build a kernel with everything enable you'll know the result is unreasonably > large. Modules allow the same kernel to work on a wide variety of large and > small machines.
It also avoids a reboot cycle when you want to debug small changes to drivers (assuming you didn't crash). Restarting a userspace app (like qemu) takes five seconds. Restarting the kernel can take a minute and change, and often involves pressing a button on a machine that's shoved under a desk and hard to get at. I've found avoiding the reboot cycle to be a nice thing with qemu (and User Mode Linux), but alas you can't test a driver for hardware qemu doesn't emulate. Nice for filesystems and VM stuff, though... Rob -- "Perfection is reached, not when there is no longer anything to add, but when there is no longer anything to take away." - Antoine de Saint-Exupery _______________________________________________ Qemu-devel mailing list Qemu-devel@nongnu.org http://lists.nongnu.org/mailman/listinfo/qemu-devel
