Re: [9fans] Regarding venti block size

[matt <mattmobile@proweb.co.uk>]

anooop.anooop@gmail.com wrote:
> Hello All,
>
> I want to store some big files on venti.  size range around 200MB.  Is
> there any way to do this?
>
> This is what I get when I try to store files of size around 300KB :
> "write: input too big: max block size is 57344"
>
> I was wondering may be if increase the block size in arena partition
> this can be done. so I tried to format arena with block size 200M but
> it gave the error below.
>
> "anoop@allatoona:/usr/local/plan9/bin$ venti/fmtarenas -a 3800M -b
> 200M  arenas0. /dev/sda6 &
> [1] 32604
> anoop@allatoona:/usr/local/plan9/bin$ block size too large, max 65536"
>

why are you choosing such a big block size ?

Blocks size and file size are related such that ceil(filesize /
blocksize) = numberofblocks

The larger the blocksize the less likely you are of coalescing any (or
that's what my intuition says). Sure, there's a tradeoff but the
research has been done already and < 64k blocks looks to have been found
appropriate.


If your file is 300Kb and your blocksize 200M then every distinct 300kB
file will occupy 200Mb of actual disk.


Also, 200Mb is not a big file!!