BIND 10 #1750: add "at origin" option in ZoneFinder::find() and support it in in-memory

[BIND 10 Development]

#1750: add "at origin" option in ZoneFinder::find() and support it in in-memory
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                   Reporter:         |                 Owner:  jinmei
  jinmei                             |                Status:  reviewing
                       Type:  task   |             Milestone:
                   Priority:  high   |  Sprint-20120501
                  Component:  data   |            Resolution:
  source                             |             Sensitive:  0
                   Keywords:         |           Sub-Project:  DNS
            Defect Severity:  N/A    |  Estimated Difficulty:  4
Feature Depending on Ticket:  auth   |           Total Hours:  0
  performance                        |
        Add Hours to Ticket:  0      |
                  Internal?:  0      |
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Comment (by jinmei):

 Replying to [comment:13 vorner]:

 > So, could you have a quick look if I did something obviously stupid in
 the merge? If not, I propose to drop the branch.

 We could at least optimize the in-memory find() internal a bit more
 (see the attached patch).  With this change, the optimized version for
 the NXDOMAIN case was about 4% faster in my local experiments.  In
 other cases or without this additional change, it's around 1%
 improvement (which is probably within margin).

 In any case, I have to admit the effect of this optimization is
 probably too marginal.  Since the change is small it may still make
 sense if we can reliably get a few percentages of improvement, but
 even if so it's probably too premature.

 So I agree with dropping the branch.  (I'm sorry that this branch
 wasted your time).

-- 
Ticket URL: <http://bind10.isc.org/ticket/1750#comment:14>
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