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From:MARK CALLAGHAN Date:February 27 2009 5:13am
Subject:Re: [Drizzle-discuss] Removing Array custom vector allocation for
semi-join subqueries
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On Thu, Feb 26, 2009 at 6:13 PM, Monty Taylor <mordred@stripped> wrote:
> Brian Aker wrote:
>> Hi!
>>
>> On Feb 26, 2009, at 12:21 PM, Mats Kindahl wrote:
>>
>>> recycling. In that case, any pointers into that old memory that are still
>>> dangling would not be useful, since the memory is likely to be
>>> overwritten with
>>
>> mem_root or not mem_root... I consider this to be pretty bad behavior to
>> rely on.
>
> Not mem_root. C++ has much better ways of dealing with this sort of
> thing (automatic delloc when you're done with stuff) mem_root was likely
> very important when it was written, and a great idea then.
>
> Now it's just extra complexity that hides behavior.
>
> Monty

My C++ skills have faded given what I work on. What does C++ have that
is similar to mem_root? That is, I want an allocator to be used with a
variety of STL classes for which I will deallocate everyting all at
once but at some random point in the future. And since I don't want to
have to retain handles to everything that has been allocated, I prefer
to invoke deallocate on the allocator rather than all of the objects
that have been allocated from it.

>
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-- 
Mark Callaghan
mdcallag@stripped
Thread
Removing Array custom vector allocation for semi-join subqueriesJay Pipes26 Feb
  • Re: Removing Array custom vector allocation for semi-join subqueriesKonstantin Osipov26 Feb
    • Re: Removing Array custom vector allocation for semi-join subqueriesJay Pipes26 Feb
  • Re: [Drizzle-discuss] Removing Array custom vector allocation forsemi-join subqueriesKonstantin Osipov26 Feb
    • Re: [Drizzle-discuss] Removing Array custom vector allocation forsemi-join subqueriesJay Pipes26 Feb
Re: [Drizzle-discuss] Removing Array custom vector allocation for semi-join subqueriesBrian Aker26 Feb
  • Re: [Drizzle-discuss] Removing Array custom vector allocation forsemi-join subqueriesMonty Taylor27 Feb
    • Re: [Drizzle-discuss] Removing Array custom vector allocation for semi-join subqueriesMARK CALLAGHAN27 Feb
      • Re: [Drizzle-discuss] Removing Array custom vector allocation forsemi-join subqueriesMonty Taylor27 Feb
        • Re: [Drizzle-discuss] Removing Array custom vector allocation forsemi-join subqueriesKonstantin Osipov27 Feb
          • Re: [Drizzle-discuss] Removing Array custom vector allocation for semi-join subqueriesMARK CALLAGHAN27 Feb
        • Re: [Drizzle-discuss] Removing Array custom vector allocation for semi-join subqueriesMARK CALLAGHAN27 Feb
          • Re: [Drizzle-discuss] Removing Array custom vector allocation forsemi-join subqueriesJim Starkey27 Feb
    • Re: [Drizzle-discuss] Removing Array custom vector allocation forsemi-join subqueriesMichael Widenius2 Mar
      • Re: [Drizzle-discuss] Removing Array custom vector allocation forsemi-join subqueriesJay Pipes2 Mar
      • Re: [Drizzle-discuss] Removing Array custom vector allocation forsemi-join subqueriesJim Starkey2 Mar
        • Re: [Drizzle-discuss] Removing Array custom vector allocation forsemi-join subqueriesKonstantin Osipov2 Mar
        • Re: [Drizzle-discuss] Removing Array custom vector allocation forsemi-join subqueriesMichael Widenius5 Mar
Re: [Drizzle-discuss] Removing Array custom vector allocation for semi-join subqueriesBrian Aker26 Feb