BIND 10 #2836: update in-memory zone loading so it can work with shmem segment

[BIND 10 Development]

#2836: update in-memory zone loading so it can work with shmem segment
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            Reporter:  jinmei        |                        Owner:
                Type:  task          |  jinmei
            Priority:  medium        |                       Status:
           Component:  data source   |  reviewing
            Keywords:                |                    Milestone:
           Sensitive:  0             |  Sprint-20130514
         Sub-Project:  DNS           |                   Resolution:
Estimated Difficulty:  4             |                 CVSS Scoring:
         Total Hours:  0             |              Defect Severity:  N/A
                                     |  Feature Depending on Ticket:
                                     |  shared memory data source
                                     |          Add Hours to Ticket:  0
                                     |                    Internal?:  0
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Changes (by vorner):

 * owner:  vorner => jinmei


Comment:

 Hello

 Before going to process your comments, I'd like to discuss something. I'm
 not
 sure this is the way forward, because catching the SegmentGrown exception
 in
 several different places in different layers of abstraction looks
 incredibly
 messy and badly designed. I fear this'll end up very buggy and such.

 Where is the layer at which point it should never get through? I believe
 we
 need to choose one such layer and not handle it below or above it. Also,
 how to
 keep up all the pointers that are cached up to date? Should we keep some
 kind
 of offsets instead?

 Also, I don't think the zone data updater can keep the named pointer
 inside it
 outside of its own functions. What if there are two updaters working on
 different zones in the same segment? Wouldn't they bother each other?

 Or, wouldn't there be a better way than the exception? The segment growing
 doesn't seem like an exceptional event to me, to tell the truth.

-- 
Ticket URL: <http://bind10.isc.org/ticket/2836#comment:12>
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