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Size of kernels



Hi,

RAM is getting cheaper and the devices I'm using right now have at least
256 MB of ram. The ramdisk-kernels have many advantages for the systems
I build the limited ramdisk-size is making it hard to get things done.
When using Flashboot and the ramdisk kernels you have a limit of
currently 14 MB if I have understand Damien's text from the flashboot
readme-file. Is this limit static or it there something that can be changed.

Rickard.


A couple of caveats regarding kernel customisation: First, if your
kernel+ramdisk blob is larger than 16Mb, then you will need to increase
NKPTP in the kernel config (just uncomment the entry in the file, it's
good for 32Mb kernels). The symptom of a kernel with a too-small NKPTP
is an immediate crash or reboot after the kernel is loaded. Another
caveat is that kernels larger than about 14Mb in size will use up all
the ISA DMA memory and the kernel will panic at boot unless isadma is
disabled in the config or via UKC. This leads to the final problem: if
isadma is disabled, then things that attempt to use it (e.g. floppy disk
access) will panic the kernel. The best solution is to try to keep your
kernels small.