On Fri, Nov 05, 2021 at 11:15:13AM +0200, u...@mailo.com wrote:
> Also asked on:
> https://unix.stackexchange.com/questions/676245/openbsd-core-dump-and-var-size
>
> I'm trying to figure out my partitioning which leads to
> https://man.openbsd.org/disklabel#AUTOMATIC_DISK_ALLOCATION
> which says:
>
> "/var 13% of disk. 80M – 2x size of crash dump"
>
> But how do I know the size of crash dump?
The point of auto-allocation is that this computation is done for you.
But a crash dump is roughly the size of your physcial mem. Actually
the max for /var is 4G *plus* 2x physical mem. So the table in the
man page is not completely right.
-Otto
> I can't find it neither in OpenBSD's installation guide, nor in
> https://man.openbsd.org/savecore.8
> nor in the internet at large.
>
> The only clue I've found is in
> http://man.openbsd.org/man8/crash.8
> "the system dumps the contents of physical memory
> onto a mass storage peripheral device"
>
> "physical memory".
> So do rules of estimating swap partition size apply here as well?
>
> May I ask for some actual numbers/functions/tables?
> Perhaps similar to the table in
> https://askubuntu.com/a/49138
> answer on swap size:
>
> Amount of RAM Swap space Swap space
> in the system if allowing for hibernation
> -------------- ---------- ---------------------------
> ≤ 2 GB 2x RAM 3x RAM
> > 2 GB – 8 GB = RAM 2x RAM
> > 8 GB – 64 GB ≥ 4 GB 1.5x RAM
> > 64 GB ≥ 4 GB Hibernation not recommended
>
> I am an ordinary user who is not going to test OpenBSD for crashiness
> but to just run it the more stable the better
> but for the possibility of a crash be able to report it.
>
>
