Rev 3723: Document the advantage of using a revision_id set, instead of a (file_id, revision_id) one. in http://bzr.arbash-meinel.com/branches/bzr/1.8-dev/lighter_log_file

[John Arbash Meinel]

At http://bzr.arbash-meinel.com/branches/bzr/1.8-dev/lighter_log_file

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revno: 3723
revision-id: john at arbash-meinel.com-20080918204343-0h7rbblut820u6i8
parent: john at arbash-meinel.com-20080918200531-woiund7811i2kgyy
committer: John Arbash Meinel <john at arbash-meinel.com>
branch nick: lighter_log_file
timestamp: Thu 2008-09-18 15:43:43 -0500
message:
  Document the advantage of using a revision_id set, instead of a (file_id, revision_id) one.
-------------- next part --------------
=== modified file 'bzrlib/log.py'
--- a/bzrlib/log.py	2008-09-18 20:05:31 +0000
+++ b/bzrlib/log.py	2008-09-18 20:43:43 +0000
@@ -573,6 +573,8 @@
     # are actually present, and then convert it back to revision_ids, since the
     # file_id prefix is shared by everything.
     text_parent_map = branch.repository.texts.get_parent_map(text_keys)
+    # Using a set of revisions instead of a set of keys saves about 1MB (out of
+    # say 400). Not a huge deal, but still "better".
     modified_text_revisions = set(key[1] for key in text_parent_map)
     del text_parent_map
     del text_keys