Re: [PATCH] cowlinks v2

From: Pavel Machek
Date: Wed Mar 31 2004 - 09:47:27 EST


> > Also it should be possible to have file with 2 hardlinks cowlinked
> > somewhere, and possibly make more hardlinks of that one... Having
> > pointer to another inode in place where direct block pointers normally
> > are should be enough (thinking ext2 here).
> Yes.
> > > But sharing data blocks without sharing inodes is too horrible even to
> > > contemplate, I suppose.
> >
> > Why, btw?
> >
> > Lets say we allocate 4 bits instead of one for block bitmap. Count
> > "15" is special, now it means "15 or higher". That means we have to
> > "garbage-collect" to free space that used to have more than 15 links,
> > but that should not happen too often...
> The garbage collection is what's horrible about it :)
> Btw, 15 would be exceeded easily in my home directory.

Well, but chances are that you'll never unlink such files... Leaving
garbage collection to fsck would make it rather easy.

> IMHO, an inode whose block pointers points to another, so that whole
> files only can be shared, would be fine.

Yes, this is probably way better way to do that.
When do you have a heart between your knees?
[Johanka's followup: and *two* hearts?]
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