[lkml]   [2003]   [Aug]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [RFC] file extents for EXT3
On Aug 11, 2003  08:53 -0400, Jeff Garzik wrote:
> Changing the underlying disk format without bumping the filesystem
> revision is a hugely bad idea. I disagreed with merging htree (even
> though its backward compat) without bumping the filesystem version, too.
> Vendors, distributors, OEMs, etc. all test against existing on-disk
> formats, when they release their products. When the filesystem format
> for an existing filesystem, in production, changes underneath them, they
> tend to get worried and annoyed. So, to all ext developers,
> Please add <it> to ext4 not ext3!

Ext2/3 uses feature flags instead of version numbers to indicate such
changes. Version numbers are a poor way of indicating whether a change
is compatible or not compared to feature flags. For example, if you bump
the minor number to indicate a "compatible" change it means that any
code that pretends to support version x.y features also needs to support
all features <= y and all features <= x.

If you really want to have a feature number to be happy, just think of


as something like a version number and you will nearly be happy.

Cheers, Andreas
Andreas Dilger

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:47    [from the cache]
©2003-2014 Jasper Spaans. hosted at Digital Ocean