[prev in list] [next in list] [prev in thread] [next in thread] 

List:       fossil-users
Subject:    Re: [fossil-users] Repo Checksum Speedup Idea: flaw in my comment
From:       Eduardo Morras <emorrasg () yahoo ! es>
Date:       2016-12-06 9:04:37
Message-ID: 20161206100437.a5b5d27fda773678dececb8c () yahoo ! es
[Download RAW message or body]

On Mon, 5 Dec 2016 20:23:50 +0200
Martin Vahi <martin.vahi@softf1.com> wrote:

> As it turns out, I already made a mistake
> at the tree based algorithm.
> 
> The old, proposed, flawed version:
> > ...
> > array_of_nodes_with_wrong_x_node_hash=unique_by_node_ID(
> > clone(
> > ob_AVL_tree.array_of_nodes_that_had_changes_on_path_2_root
> > ).concat(clone(
> > ob_AVL_tree.array_of_nodes_that_have_changed_children
> > // change within children means that any
> > // of the children changed during the insertion
> > // or removal of nodes to/from the ob_AVL_tree
> > // after the AVL-tree got (automatically) rebalanced.
> > // A change between null and an existing child is
> > // also considered a change.
> > ))
> > ).sort_by_path_length_from_node_to_root_node
> > 
> > ...
> 
> A newer version looks only the changes within
> children:
> 
> array_of_nodes_with_wrong_x_node_hash=unique_by_node_ID(
> clone(
> ob_AVL_tree.array_of_nodes_that_have_changed_children
> )).sort_by_path_length_from_node_to_root_node

Do you mean a Tree Hash like in dc/adc, bittorrent, emule/edonkey ?  They use TTH \
(Tiger Tree Hash), computing hashs of chunks/flie parts, and from them calculates \
hash of groups of hashes. This way they know in logN steps what chunk is corrupted, \
and download again. 

If yes, I don't think it could replace current checksum. It solves a different \
problem.

If no, I'll reread your mails.

> Thank You.


---   ---
Eduardo Morras <emorrasg@yahoo.es>
_______________________________________________
fossil-users mailing list
fossil-users@lists.fossil-scm.org
http://lists.fossil-scm.org:8080/cgi-bin/mailman/listinfo/fossil-users


[prev in list] [next in list] [prev in thread] [next in thread]