kernelconfig_penguin
CONFIG_4KSTACKS is not available for the default architecture x86.
Result is shown for architecture sh
depends
CONFIG_DEBUG_KERNEL
NOT CONFIG_PAGE_SIZE_64KB
CONFIG_BROKEN or 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. This option
will also use IRQ stacks to compensate for the reduced stackspace.