BIND 10 #1399: auth per opcode statistics

[BIND 10 Development]

#1399: auth per opcode statistics
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                   Reporter:         |                 Owner:  jinmei
  jinmei                             |                Status:  accepted
                       Type:  task   |             Milestone:
                   Priority:  major  |  Sprint-20120110
                  Component:         |            Resolution:
  statistics                         |             Sensitive:  0
                   Keywords:         |           Sub-Project:  DNS
            Defect Severity:  N/A    |  Estimated Difficulty:  3
Feature Depending on Ticket:  Auth   |           Total Hours:  0
  statistics                         |
        Add Hours to Ticket:  0      |
                  Internal?:  0      |
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Comment (by jinmei):

 trac1399 is ready for review.

 While I looked at the code thinking about how I'd implement it, I was
 tempted to introduce a more generic framework for supporting various
 types of statistics counters and do this task on top of it.  But,
 realizing that it would be a quite large task and we still don't have
 any user visible update in statistics since the last release, I chose
 a kind of ad hoc approach: adding some specific methods to the auth
 and counter classes for this purpose.

 I guess we should revisit the entire design and the currently added
 code (and perhaps even how we present these counters) will be obsolete
 at that point, but I thought it's still nice to show how we are going
 to support more counters.

 As long as this approach is acceptable, I believe the implementation
 itself is quite straightforward.  (And I want it to be included in the
 next release)

 This is the proposed changelog entry:
 {{{
 360.?   [func]          jinmei
         b10-auth experimentally supports statistics counters of incoming
         requests per opcode.  The counters can be (e.g.) shown as
         opcode.<code name> in the output of the bindctl "Stats show"
         command, where <code name> is lower-cased textual representation
         of opcodes ("query", "notify", etc).
         Note: This is an experimental attempt of supporting more
         statistics counters for b10-auth, and the interface and output may
         change in future versions.
         (Trac #1399, git TBD)
 }}}

 p.s. I've noticed various issues in the statistics framework in
 general by handling this task, so even if my attempt of the
 implementation is in vain, the effort won't be:-)

-- 
Ticket URL: <http://bind10.isc.org/ticket/1399#comment:7>
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