Subject: Re: Finally increasing vm.execmin by default
To: Gavan Fantom <gavan@coolfactor.org>
From: Chuck Swiger <cswiger@mac.com>
List: netbsd-users
Date: 10/28/2005 15:27:08
Gavan Fantom wrote:
> Todd Vierling wrote:
[ ... ]
>> If a system has many GiB of memory, it should be up to the admin to lower
>> the execmin in order to gain yet more fs or anon page cache.  It should
>> *not* be up to the users of systems with modest memory to raise them.
> 
> This says to me that the variables themselves could do with a rethink, 
> not just the default values. Perhaps there's something other than a 
> percentage that makes for a better constant default?
> 
> How does the ideal size of execmin (and, perhaps the other mins) vary 
> with total system memory size?

It depends on load and the variety of programs being run.  A machine like a 
mailserver or a DNS server might only run a small number of programs, whereas 
an end-user workstation running KDE and lots of eyecandy might want an order of 
magnitude more room for text pages.

[ Delurks long enough to mutter something about looking at the global page 
fault frequency rate of the various page types, and trying to minimize that. 
Easier said than coded. :-) ]

-- 
-Chuck