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Am Donnerstag, 7. September 2017, 17:46:27 CEST schrieb Helmut Jarausch: |
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> Hi, |
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> |
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> sorry, this question is not Gentoo specific - but I know there are many |
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> very knowledgeable people on this list. |
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> |
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> I'd like to "hard-link" a file X to Y - i.e. there is no additional |
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> space on disk for Y. |
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> |
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> But, contrary to the "standard" hard-link (ln), file Y should be stored |
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> in a different place (inode) IF it gets modified. |
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> With the standard hard-link, file X is the same as Y, so any changes to |
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> Y are seen in X by definition. |
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> |
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> Is this possible |
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> - with an ext4 FS |
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> - or only with a different (which) FS |
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|
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This has come to be referred to as reflinks (see, e.g., the cp(1) man page). |
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I don't think ext4 supports them, but both btrfs and xfs do (xfs only very |
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recently, though, see for example [0]). There might be other FSs that support |
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it, too (bcachefs?), but I don't know about that. |
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|
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Maybe at some point ext4 will add support for it, but since I mainly use btrfs |
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I don't care that much. |
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|
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[0] http://strugglers.net/~andy/blog/2017/01/10/xfs-reflinks-and-deduplication/ |
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> Many thanks for a hint, |
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> Helmut |
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|
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HTH |
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-- |
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Marc Joliet |
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-- |
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"People who think they know everything really annoy those of us who know we |
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don't" - Bjarne Stroustrup |
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