RELENG_4 on flash disk and swap

[Michael Proto]

In this case I'd just ignore swap. Since /dev/md0 is only a memory disk
anyway, you don't really buy anything by having it as swap as opposed to
unallocated RAM. Just make sure that all your running programs are able
to fit in the 256Mb of RAM you have, otherwise processes will fail to
start or others will die when they need to allocate additional RAM.

I'm running FreeBSD in 64Mb with no swap and it works fine. A few
sysctls that I've found helpful for running without swap:

vm.swap_enabled=0
vm.disable_swapspace_pageouts=1
kern.ipc.shm_use_phys=1


-Proto

Dmitry Pryanishnikov wrote:
> Hello!
> 
>   Suppose I have machine with 256Mb of RAM and 256Mb flash ATA
disk-on-module.
> What configuration (using RELENG_4) should I select:
> 
> 1. No swap at all.
> 2. /dev/md0 (default 10Mb) added as a swap device.
> 
> In other words, does RELENG_4 kernel work stable and robust w/o swap or
> should I provide a minimum-size swap device? Which configuration (1 or 2)
> will give more robustness in case of physical memory shortage?
> 
> Sincerely, Dmitry