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SubjectKernel memory usage optimisations?

I'm working on a project that uses Linux kernel version 2.4.16 on an
embedded ARM device. Since we have limited memory (both RAM and Flash) I
have tuned down some kernel internal defines to make it use less memory:

include/linux/major.h: MAX_CHRDEV 255->20, MAX_BLKDEV 255->10
include/linux/tty.h: MAX_NR_CONSOLES 63->3, MAX_NR_USER_CONSOLES 63->3
include/linux/kernel-stat.h: DK_MAX_MAJOR 16->4, DK_MAX_DISK 16->4
include/linux/sched.c: PIDHASH_SZ 1024->16
include/linux/tty.h: NR_PTYS 256->16, NR_LDISCS 16->4
kernel/printk.c: LOG_BUF_LEN 16384->2048

With these I have saved about 100 KB from bss. Do you see any dangerous
side-effects in those modifications?

I understand that best area for saving memory usage is the C-library but
are there any other kernel areas? I'm thinking of dropping swapfile support
and maybe some other subsystems that are not needed in embedded device.

Marko Kenttälä, Software Engineer
TERAFLOPS Ltd., Member of Elektrobit Group
Mobile: +358 40 7501832, Fax: +358 3 2258484,

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