[Date Prev][Date Next][Thread Prev][Thread Next] [Search] [Date Index] [Thread Index]

Re: [MacPerl] DB_File and odd behaivor



At 09:16 +0200 98/06/16, Matthias Ulrich Neeracher wrote:
> Hmm, in that case, I think I know what's wrong with DB_File: It won't work
> reliably on file systems where the logical block size is not a power of
>2.

> That the size, written as a binary number, contains exactly one "1".

Herewith the HFS (minus? :-) disk block allocation table for disk volume
sizes from 32 MB to 1 GB (if yours is bigger, I trust you can work it
out...)

If I understand Matthias arightly, the rows with nothing in the "power of 2"
column will be problematic (I didn't compute the ones where the exponent
has a fraction)

volume        alloc. block      power of 2
size (MB) 		 size
32                     512              2^9
64                   1024              2^10
96                   1536              -
128                 2048              2^11
160                 2560              -
192                 3072              -
224                 3584              -
256                 4096              2^12
288                 4608              -
320                 5120              -
352                 5632              -
384                 6144              -
416                 6656              -
448                 7168              -
480                 7680              -
512                 8192              2^13
544                 8704              -
576                 9216              -
608                 9728              -
640              10240              -
672              10752              -
704              11264              -
736              11776              -
768              12288              -
800              12800              -
832              13312              -
864              13824              -
896              14336              -
928              14848              -
960              15360              -
992              15872              -
1024            16384              2^14
---
Vicki Brown, vlb@cfcl.com        |\      _,,,---,,_
Journeyman Sourceror      ZZZzz /,`.-'`'    -.  ;-;;,_
Scripts & Philtres             |,4-  ) )-,_. ,\ (  `'-'
http://www.cfcl.com/~vlb      '---''(_/--'  `-'\_)
P.O. Box 1269 San Bruno, CA  94066

***** Want to unsubscribe from this list?
***** Send mail with body "unsubscribe" to mac-perl-request@iis.ee.ethz.ch