From: Magne Mæhre
Date: November 19 2010 4:52pm
Subject: Re: bzr commit into mysql-next-mr-bugfixing branch (magne.mahre:3328)
 Bug#49177
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On 11/19/2010 05:22 PM, Sergey Vojtovich wrote:
> Magne,
> 
> ok, do you think it is worth to consider that we may rework
> this part sooner or later and make less intrusive patch?

Hi Sergey / Mattias

I'm not entirely sure I follow you.   What the patch does is
simply to exchange one data structure with another.  Since the
container classes in mysql doesn't provide a common interface,
there is a need to change some code.  Most of the code change
is in peripheral functions (mi_panic, debugging, etc.), where
there is a need to traverse all stored objects.  I also had to
do some extra initialization, since the MyISAM code is also used
directly from supporting tools, which does not use the
handlerton.

I feel that this solution is fairly good, as a trade-off
between speed, complexity and implementation risk.  It is
entirely possible to get an even faster lookup mechanism
than this, but I feel it's not worth the extra effort.  The
benchmarking we did, show a tremendous(!) improvement over the
old implementation (see my _private_ entry on the bug report
page, dated Sep. 30th)

Since WL#4305 isn't, to my knowledge, started on yet, it means
the impact on that work is minimal.  What is absolutely certain
is that we won't be using the old iterate-and-compare-name-string
approach in that worklog, so I believe something like my patch
will naturally find its place in that code.

Of course, I'm open to suggestions on how to improve the code,
and other approaches.  I am, however, reluctant to have code
living in my sandbox, while waiting for a worklog that has
unknown priority, and might even be stopped (not that I
have any indications on that happening :)

So - to sum it up --  I'm, of course, very eager to get this
patch in.  I'm, on the other hand, ready to accept it if it is
thought to be a bad idea :)

--Magne