Re: File BlockSize

Rik van Riel (riel@conectiva.com.br)
Tue, 12 Feb 2002 20:00:41 -0200 (BRST)

On Tue, 12 Feb 2002, William Lee Irwin III wrote:
> On Tue, Feb 12, 2002 at 02:37:43PM +0000, Alan Cox wrote:
> > Going to a block size bigger than page size causes all sorts of fun with
> > allocation failures if there are not two pages free adjacent to one another
> > when allocating, and isn't really worth the cost.
>
> This sounds like fairly severe memory fragmentation, which seems more
> worrisome to me than blocksize constraints. Should I look into that?

Sorry for being dense, but I don't see why an 8 kB block would
need to occupy 2 contiguous pages in ram.

The page cache is indexed in pages, it should be easy enough to
do the disk IO on the 8 kB on-disk block as 2 4 kB IOs, each to
a different page in RAM.

regards,

Rik

-- 
"Linux holds advantages over the single-vendor commercial OS"
    -- Microsoft's "Competing with Linux" document


http://www.surriel.com/		http://distro.conectiva.com/


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