kernelconfig_penguin
CONFIG_4KSTACKS is not available for the default architecture x86.
Result is shown for architecture m68k
depends
CONFIG_COLDFIRE or  NOT CONFIG_MMU

Use 4Kb for kernel stacks instead of 8Kb

configname: CONFIG_4KSTACKS

Linux Kernel Configuration
└─> Use 4Kb for kernel stacks instead of 8Kb

If you say Y here the kernel will use a 4Kb stacksize for the
kernel stack attached to each process/thread. This facilitates
running more threads on a system and also reduces the pressure
on the VM subsystem for higher order allocations.