[Xapian-tickets] [Xapian] #671: Performance issues when querying over large number of local databases (shards)

[Xapian]

#671: Performance issues when querying over large number of local databases
(shards)
----------------------------------+-----------------------------
 Reporter:  wgreenberg            |             Owner:  olly
     Type:  defect                |            Status:  assigned
 Priority:  normal                |         Milestone:  1.3.4
Component:  Matcher               |           Version:
 Severity:  normal                |        Resolution:
 Keywords:  sharding performance  |        Blocked By:
 Blocking:                        |  Operating System:  Linux
----------------------------------+-----------------------------

Comment (by olly):

 Incidentally, looking at attachment:ordered_strace.log I notice there are
 two reads from each postlist table as the shards are opened.  I think the
 second read must be getting the database stats, which back then were
 stored as an entry in the postlist table.  These are now stored in the
 "version file", so that probably means we now avoid that extra read (and
 if the tables have more levels, there would have been multiple reads for
 each postlist table to get that information).

--
Ticket URL: <http://trac.xapian.org/ticket/671#comment:16>
Xapian <http://xapian.org/>
Xapian