Recommended amount of swap

Dan Nelson dnelson at allantgroup.com
Mon Sep 5 23:15:36 UTC 2011


In the last episode (Sep 05), Eitan Adler said:
> On Mon, Sep 5, 2011 at 3:48 PM, Dan Nelson <dnelson at allantgroup.com> wrote:
> > In the last episode (Sep 05), Sean Hamilton said:
> >> What is the state of the art for the recommended amount of swap in
> >> FreeBSD? Both "normal" systems with 512 MB - 8 GB of RAM, and large
> >> database systems with around 128 - 256 GB.
> 
> Keep in mind that you need at least ram = swap to get a coredump.

Not if debug.minidump is set to 1, which it is by default.  In that case,
only mapped memory gets dumped, which should ignore disk cache pages and be
a lot smaller than your RAM size.  Enabling ZFS may make your dumps bigger
unless the minidump code is smart enough to not dump the ARC.

-- 
	Dan Nelson
	dnelson at allantgroup.com


More information about the freebsd-hackers mailing list