Path: utzoo!attcan!uunet!tektronix!sequent!djg
From: djg@sequent.UUCP (Derek Godfrey)
Newsgroups: comp.unix.wizards
Subject: Re: System V file systems
Summary: multiple block sizes
Message-ID: <6933@sequent.UUCP>
Date: 31 Oct 88 16:03:39 GMT
References: <6413@daver.UUCP> <8332@alice.UUCP> <1988Oct27.173247.2789@utzoo.uucp> <917@vsi.COM>
Organization: Sequent Computer Systems, Beaverton, OR
Lines: 15

> How hard is it for an instantiation of UNIX to support multiple
> kinds of blocksizes?  I would think that keeping the blocksize in
> the superblock would make it pretty easy, so I could use 1k blocks
> for root, and (say) 8k for the /database partition with a dozen
> files all > 1MB.  Currently it seems like a big deal for them
> to come out with a new supported blocksize.
> 

Not difficult at all since the block size field of the super block is
32 bits wide. The code needed in fs/s5 is minimal - just changing a
few case statements to an alogrithm! (assuming you'r willing to increase the
size of a system buffer) The biggest effort however is
converting all the utilities that are still using BSIZE rather then
FsBSIZE.