gnus: Gnus Registry Setup

 
 9.18.1 Gnus Registry Setup
 --------------------------
 
 Fortunately, setting up the Gnus registry is pretty easy:
 
      (setq gnus-registry-max-entries 2500)
 
      (gnus-registry-initialize)
 
    This adds registry saves to Gnus newsrc saves (which happen on exit
 and when you press ‘s’ from the ‘*Group*’ buffer.  It also adds registry
 calls to article actions in Gnus (copy, move, etc.) so it’s not easy to
 undo the initialization.  See ‘gnus-registry-initialize’ for the gory
 details.
 
    Here are other settings used by the author of the registry
 (understand what they do before you copy them blindly).
 
      (setq
       gnus-registry-split-strategy 'majority
       gnus-registry-ignored-groups '(("nntp" t)
                                      ("nnrss" t)
                                      ("spam" t)
                                      ("train" t))
       gnus-registry-max-entries 500000
       ;; this is the default
       gnus-registry-track-extra '(sender subject))
 
    They say: keep a lot of messages around, track messages by sender and
 subject (not just parent Message-ID), and when the registry splits
 incoming mail, use a majority rule to decide where messages should go if
 there’s more than one possibility.  In addition, the registry should
 ignore messages in groups that match “nntp”, “nnrss”, “spam”, or
 “train.”
 
    You are doubtless impressed by all this, but you ask: “I am a Gnus
 user, I customize to live.  Give me more.” Here you go, these are the
 general settings.
 
  -- Variable: gnus-registry-unfollowed-groups
      The groups that will not be followed by
      ‘gnus-registry-split-fancy-with-parent’.  They will still be
      remembered by the registry.  This is a list of regular expressions.
      By default any group name that ends with “delayed”, “drafts”,
      “queue”, or “INBOX”, belongs to the nnmairix backend, or contains
      the word “archive” is not followed.
 
  -- Variable: gnus-registry-max-entries
      The number (an integer or ‘nil’ for unlimited) of entries the
      registry will keep.  If the registry has reached or exceeded this
      size, it will reject insertion of new entries.
 
  -- Variable: gnus-registry-prune-factor
      This option (a float between 0 and 1) controls how much the
      registry is cut back during pruning.  In order to prevent constant
      pruning, the registry will be pruned back to less than
      ‘gnus-registry-max-entries’.  This option controls exactly how much
      less: the target is calculated as the maximum number of entries
      minus the maximum number times this factor.  The default is 0.1:
      i.e., if your registry is limited to 50000 entries, pruning will
      try to cut back to 45000 entries.  Entries with keys marked as
      precious will not be pruned.
 
  -- Variable: gnus-registry-default-sort-function
      This option specifies how registry entries are sorted during
      pruning.  If a function is given, it should sort least valuable
      entries first, as pruning starts from the beginning of the list.
      The default value is ‘gnus-registry-sort-by-creation-time’, which
      proposes the oldest entries for pruning.  Set to nil to perform no
      sorting, which will speed up the pruning process.
 
  -- Variable: gnus-registry-cache-file
      The file where the registry will be stored between Gnus sessions.
      By default the file name is ‘.gnus.registry.eieio’ in the same
      directory as your ‘.newsrc.eld’.