[Paul Winkler]
Our experiments suggest that ext2, ext3, and reiserfs optimize for sparse files so there is no such guarantee. AFAICT from some quick googling and wikipediaing, the same is true for NTFS, XFS, JFS, ZFS. I suspect we've accounted for the majority of the production Zope installations in the world.
[Benji York]
In that case it would seem better to just remove the ineffectual code altogether.
[Jim Fulton]
+1
-0. See my other response. +1 on beefing up the comment, though. On all systems the code does no harm and does /inform/ the OS of how large a file is needed. At least on NTFS it also does all that reasonably can be done to ensure enough space actually exists (while NTFS supports sparse files, it's not the default, and the ZEO code does not create a sparse file under NTFS). The Windows behavior could be effectively gotten on most other platforms by adding a loop to write a non-NUL byte to every (say) 512th byte position. This would be redundant on Windows (NTFS physically writes NUL bytes to every "missing" position in a dense file whenever the EOF pointer advances), but would do no harm there either. Or it could be that people are happy to have ZEO blow up later ;-) _______________________________________________ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org http://mail.zope.org/mailman/listinfo/zodb-dev
