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From:Tomalak Geret'kal Date:March 23 2011 10:07am
Subject:Re: StoreQueryResults destructor runs without end...
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On 23/03/2011 09:08, Warren Young wrote:
> Keep in mind also the behavior of std::vector, which StoreQueryResult is based on. 
> (More or less, it is a 2D vector of mysqlpp::String.)  It doubles in size each time you
> exceed its size, so it can keep growing.  That means lots of RAM copies for such a large
> number of fields.
>
> You can solve some of that by calling res.reserve(N), where N is larger than the
> number of records possible from the query, but you still have to deal with the fact that
> you're trying to store all that in RAM at once.

It's not necessarily strictly doubled.

I don't see why you'd ever reserve *more* than the number of 
records possible from your query. What a pointless waste of 
space. If anything, you'd reserve *exactly* the number of 
records possible.

Tom
Thread
StoreQueryResults destructor runs without end...Paul Dalach22 Mar
Re: StoreQueryResults destructor runs without end...Dino Korah22 Mar
  • Re: StoreQueryResults destructor runs without end...Paul Dalach23 Mar
    • Re: StoreQueryResults destructor runs without end...Warren Young23 Mar
      • Re: StoreQueryResults destructor runs without end...Warren Young23 Mar
        • Re: StoreQueryResults destructor runs without end...Tomalak Geret'kal23 Mar
          • Re: StoreQueryResults destructor runs without end...Mickael Wolff23 Mar
            • Re: StoreQueryResults destructor runs without end...Tomalak Geret'kal23 Mar
              • Re: StoreQueryResults destructor runs without end...Mickael Wolff23 Mar
                • Re: StoreQueryResults destructor runs without end...Tomalak Geret'kal23 Mar
          • Re: StoreQueryResults destructor runs without end...Warren Young23 Mar
            • Re: StoreQueryResults destructor runs without end...Tomalak Geret'kal23 Mar
              • List etiquette - please use good email subjects :)Joel Fielder23 Mar
                • Re: List etiquette - please use good email subjects :)Tomalak Geret'kal23 Mar
                  • Re: List etiquette - please use good email subjects :)Paul Dalach23 Mar
                    • Re: List etiquette - please use good email subjects :)Dino Korah23 Mar
                      • Re: StoreQueryResults destructor runs without end...Paul Dalach23 Mar
                      • Re: StoreQueryResults destructor runs without end...F.N. Bruggeman23 Mar
                    • Re: List etiquette - please use good email subjects :)Joel Fielder23 Mar
              • Re: growth behavior of std::vectorWarren Young23 Mar
                • Re: growth behavior of std::vectorTomalak Geret'kal23 Mar
                  • Re: growth behavior of std::vectorJonathan Wakely23 Mar
                    • Re: (OT) growth behavior of std::vectorTomalak Geret'kal23 Mar
                      • Re: (OT) growth behavior of std::vectorJonathan Wakely23 Mar
                • Re: (OT) growth behavior of std::vectorTomalak Geret'kal23 Mar
            • Re: StoreQueryResults destructor runs without end...Tomalak Geret'kal23 Mar
              • re: (OT) growth behaviour of std::vector [was Re: StoreQueryResultsdestructor runs without end...]Tomalak Geret'kal23 Mar
        • Re: StoreQueryResults destructor runs without end...Warren Young23 Mar
Re: StoreQueryResults destructor runs without end...Dino Korah23 Mar