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  • Committer: John Arbash Meinel
  • Date: 2008-10-09 20:54:50 UTC
  • mto: This revision was merged to the branch mainline in revision 3805.
  • Revision ID: john@arbash-meinel.com-20081009205450-z4k6rnvj5j1tqcmu
Fix the logic a bit, and add a bit more tweaking opportunities

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bzrlib/btree_index.py
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        # return node_indexes
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        # TODO: This could be cached
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        recommended_read = self._transport.recommended_page_size() / 4
 
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        recommended_read = self._transport.recommended_page_size()
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        recommended_pages = int(math.ceil(recommended_read /
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                                          float(_PAGE_SIZE)))
 
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        # Disable the algorithm
 
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        # recommended_pages = 1
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        if len(node_indexes) >= recommended_pages:
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            # Don't add more, we are already requesting more than enough
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            return node_indexes
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        if self._root_node is not None:
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            cached_nodes.add(0)
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        # if len(cached_nodes) < 2: # We haven't read enough to justify expansion
 
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        #     return node_indexes
 
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        # If reading recommended_pages would read the rest of the index, just
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        # do so.
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        if max_page - len(cached_nodes) <= recommended_pages:
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            #         if len(final_nodes) >= recommended_pages:
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            #             break
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        else:
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            while len(final_nodes) < recommended_pages:
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                for pos in sorted(final_nodes):
 
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            new_tips = set(final_nodes)
 
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            while len(final_nodes) < recommended_pages and new_tips:
 
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                next_tips = set()
 
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                for pos in sorted(new_tips):
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                    if pos > 0:
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                        previous = pos - 1
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                        if previous not in cached_nodes:
 
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                        if (previous not in cached_nodes
 
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                            and previous not in final_nodes):
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                            final_nodes.add(previous)
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                    if pos < max_page:
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                        after = pos + 1
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                        if after not in cached_nodes:
 
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                            next_tips.add(previous)
 
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                    after = pos + 1
 
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                    if after < max_page:
 
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                        if (after not in cached_nodes
 
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                            and after not in final_nodes):
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                            final_nodes.add(after)
 
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                            next_tips.add(previous)
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                    # if len(final_nodes) > recommended_pages:
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                    #     break
 
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                new_tips = next_tips
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        final_nodes = sorted(final_nodes)
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        trace.note('\t\t\t\t%s', final_nodes)
 
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        trace.note('\t\t%s', final_nodes)
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        return final_nodes
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    def _get_nodes(self, cache, node_indexes):
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            except KeyError:
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                needed.append(idx)
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        if not needed:
 
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            # trace.note('cached: %s\tnodes: %s', self._name[-14:], node_indexes)
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            return found
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        needed = self._expand_nodes(needed)
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        found.update(self._cache_nodes(needed, cache))
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                    self._size = len(start)
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                    size = min(_PAGE_SIZE, self._size)
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            else:
 
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                if offset > self._size:
 
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                    raise AssertionError('tried to read past the end'
 
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                                         ' of the file %s > %s'
 
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                                         % (offset, self._size))
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                size = min(size, self._size - offset)
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            ranges.append((offset, size))
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        if not ranges: