Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 4 Feb 2003 08:40:34 -0800
From:      Ryan Dooley <ryan@third-man.com>
To:        David Schultz <dschultz@uclink.Berkeley.EDU>
Cc:        Ryan Dooley <ryan@third-man.com>, stable@FreeBSD.ORG
Subject:   Re: recommendations on the newfs of a 1.0TB fs...
Message-ID:  <20030204164034.GA16030@elvis.mu.org>
In-Reply-To: <20030204053133.GA4802@HAL9000.homeunix.com>
References:  <20030203194828.GA55143@elvis.mu.org> <20030204043726.GA4323@HAL9000.homeunix.com> <20030204050631.GB81935@elvis.mu.org> <20030204053133.GA4802@HAL9000.homeunix.com>

next in thread | previous in thread | raw e-mail | index | archive | help
> When you say ``the default wasted too much disk space'', do you
> mean that when you formatted the filesystem, you had less space
> than you expected, or do you mean that there was less space left
> after you put all of your data on it?  Smaller block sizes mean
> more space for free block bitmaps, which are allocated at
> filesystem creation time, but overall they are a win in terms of
> space because of reduced internal fragmentation.  Consider what
> happens when you put a 10K file on the disk.  Depending on whether
> the filesystem is optimizing for space or time, that file will
> take up 16K or 64K in your 64/16 filesystem, but substantially
> less with a 16/2 FS.  So unless you are expecting most of your
> files to be rather large, a smaller block size may be beneficial.
> Note, however, that I'm not an FFS expert; other factors such as
> fragmentation may be relevant.

The formatted file system had less total available space left on it.  Now
it was like 5am and I'd been up for the past 24 hours setting things up
two years ago so it's a bit fuzzy :-)

Right now the FS is optimizing for time.

I had read some where (I'll see if I can dig up my notes), but I remember
getting the distinct feeling that the larger block size was what I wanted,
but like I said, it's all a bit fuzzy.


> I would also be interested in knowing how FFS and reiserfs compare
> with respect to filesystem age.  Does performance drop
> significantly after a year?  If the research I've seen is right,
> FFS performance shouldn't drop more than 20% unless the filesystem
> is nearly full, and reiserfs has a cleaner...

I'll see about running some dbench marks or bonnie and see how things
shape up.

Cheers,
	Ryan

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-stable" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20030204164034.GA16030>