[Xapian-tickets] [Xapian] #326: Searches with chert are slow, due to slow doclen access

[Xapian]

#326: Searches with chert are slow, due to slow doclen access
---------------------------+------------------------------------------------
 Reporter:  richard        |        Owner:  richard  
     Type:  defect         |       Status:  assigned 
 Priority:  normal         |    Milestone:  1.1.0    
Component:  Backend-Chert  |      Version:  SVN trunk
 Severity:  normal         |   Resolution:           
 Keywords:                 |    Blockedby:           
 Platform:  All            |     Blocking:           
---------------------------+------------------------------------------------

Comment(by richard):

 I'd be happy to sacrifice a bit of index-time performance for better
 search speed...

 I wondered about just adding a few skip positions; perhaps every storing
 the offset of every 10th docid in the list (together with the difference
 between each 10th docid), so a skip_to() would skip to the right group of
 10, and then skip to the right individual item.

 This could be done heirarchically, and could pick the offset
 probabilistically.  This is basically a skip-list, as described in
 http://en.wikipedia.org/wiki/Skip_list

-- 
Ticket URL: <http://trac.xapian.org/ticket/326#comment:7>
Xapian <http://xapian.org/>
Xapian