Returning User With Filesystem/Memory Tuning Questions

Kevin Monceaux Kevin at RawFedDogs.net
Wed Dec 3 11:46:45 PST 2008


FreeBSD Fans,

I think I've just about talked myself into coming back for another try. 
I've been a Linux user since the 1.x kernel days.  I've tried switching my 
home desktop box to FreeBSD a couple of times now.  The first time around 
was mainly to give ZFS a try.  After getting tired of ZFS related crashes 
I ended up going back to Linux.  After ZFS progressed a bit, and I had 
taken lots of notes on the tuning needed to make ZFS relatively happy, I 
tried again.  That time around I got ZFS working fairly well but eventually 
got fed up with the lack of a stable flash plugin.  On the one hand, I 
hate sites that try to force flash upon users.  On the other hand, if 
someone sends me a link to an amusing sounding YouTube video or I want to 
view the radar map at Weather.com, etc., it's a pain to be among the flash 
impaired.  I've been browsing the mailing lists from time to time and it 
sounds like flash is working well enough for the limited times I'd use it, 
so I'm considering giving it one more try.

With any of the following questions any suggestions, including RTSM(Read 
The Smeggin Manual) suggestions, are welcomed.  With RTSM suggestions, 
they are even more welcomed if they include which manual and section to 
read.  :-)

First, to ZFS or not to ZFS, that is the question.  While I like some of 
the features ZFS has to offer, I realize it may be overkill for my needs. 
The main thing I'm looking for is the ability to combine all the space 
available on both hard drives of my home desktop box.  One drive is 120GB 
and the other is 250GB.  Well, actually, I think those are marketing 
gigabytes.  I'd be happy with either having all the space combined and 
available to the root filesystem, or a separate UFS root filesystem and 
the remaining space available for everything else.  The last time around I 
set up root on UFS + /var, /usr, /home, /tmp, etc., on ZFS using 
instructions which I think were located at:

http://wiki.FreeBSD.org/JeremyChadwick/FreeBSD_7.x_on_a_ZFS_pool

though that page appears to no longer exist.  Could something like gvinum 
or gconcat be used to achieve the above or should I go with ZFS?  The box 
in question is a hyperthreaded Pentium 4 with 3GB of RAM.  If ZFS is a 
good choice, could someone point me towards the current tuning 
recommendations for ZFS?

If I remember correctly, the last time around I had some occasional memory 
related application crashes.  For example I had pan crash a few times 
trying to open a large newsgroups.  At the times of the crashes it 
appeared there was still plenty of free RAM and swap space was never even 
touched.  I know FreeBSD doesn't blindly allocate memory like Linux does, 
but I would like to tune things to take full advantage of my available 
memory.  I searched Google and tweaked some settings, though I forget 
which ones, which helped but didn't completely eliminate the crashes. 
What settings should I be looking at to tune to make the best use of my 
3GB of memory and swap space.  The last time around I set up quite a bit 
of swap space and it didn't appear to ever be touched.  I want to keep 
swapping to a minimum but would prefer to have a little swapping going on 
than to have a program crash trying to allocate memory when there's both 
RAM and swap space available.

Taking the above filesystem question into consideration, and wanting a 
stable flash plugin, which FreeBSD version should I be going with?  I 
forget what I was running last time, but RELENG_7 sounds familiar.  Is the 
7.1-BETA2 iso recent enough or do I need to go with some flavor of STABLE 
or CURRENT?



Kevin
http://www.RawFedDogs.net
http://www.WacoAgilityGroup.org
Bruceville, TX

Si hoc legere scis nimium eruditionis habes.
Longum iter est per praecepta, breve et efficax per exempla!!!



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