Merged revisions 286112 via svnmerge from

Merged revisions 286112 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.8

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  r286112 | russell | 2010-09-10 15:31:58 -0500 (Fri, 10 Sep 2010) | 9 lines

  Rate limit calls to fsync() to 1 per second after astdb updates.

  Astdb was determined to be one of the most significant bottlenecks in SIP
  registration processing.  This patch improved the speed of an astdb load
  test by 50000% (yes, Fifty-Thousand Percent).  On this particular load test
  setup, this doubled the number of SIP registrations the server could handle.

  Review: https://reviewboard.asterisk.org/r/825/
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@286498 65c4cc65-6c06-0410-ace0-fbb531ad65f3