Re: User concurrency thresholding: where do I look?

От: Tom Lane
Тема: Re: User concurrency thresholding: where do I look?
Дата: ,
Msg-id: 20297.1184991970@sss.pgh.pa.us
(см: обсуждение, исходный текст)
Ответ на: Re: User concurrency thresholding: where do I look?  (David Boreham)
Список: pgsql-performance

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User concurrency thresholding: where do I look?  (Josh Berkus, )
 Re: User concurrency thresholding: where do I look?  ("Joshua D. Drake", )
 Re: User concurrency thresholding: where do I look?  (Alvaro Herrera, )
  Re: User concurrency thresholding: where do I look?  (Josh Berkus, )
   Re: User concurrency thresholding: where do I look?  (Tom Lane, )
    Re: User concurrency thresholding: where do I look?  (Alvaro Herrera, )
     Re: User concurrency thresholding: where do I look?  (Tom Lane, )
      Re: User concurrency thresholding: where do I look?  (Josh Berkus, )
       Re: User concurrency thresholding: where do I look?  (Tom Lane, )
        Re: User concurrency thresholding: where do I look?  (Josh Berkus, )
         Re: User concurrency thresholding: where do I look?  ("Jignesh K. Shah", )
          Re: User concurrency thresholding: where do I look?  ("Jignesh K. Shah", )
          Re: User concurrency thresholding: where do I look?  (Tom Lane, )
           Re: User concurrency thresholding: where do I look?  ("Jignesh K. Shah", )
            Re: User concurrency thresholding: where do I look?  (Tom Lane, )
             Re: User concurrency thresholding: where do I look?  ("Jignesh K. Shah", )
              Re: User concurrency thresholding: where do I look?  (Tom Lane, )
               Re: User concurrency thresholding: where do I look?  ("Jignesh K. Shah", )
                Re: User concurrency thresholding: where do I look?  (Tom Lane, )
                 Re: User concurrency thresholding: where do I look?  ("Jignesh K. Shah", )
                 Re: User concurrency thresholding: where do I look?  (David Boreham, )
                  Re: User concurrency thresholding: where do I look?  (Tom Lane, )
                 Re: User concurrency thresholding: where do I look?  ("Simon Riggs", )
                  Re: User concurrency thresholding: where do I look?  (Tom Lane, )
                   Re: User concurrency thresholding: where do I look?  ("Simon Riggs", )
                    Re: User concurrency thresholding: where do I look?  (Tom Lane, )
                     Re: User concurrency thresholding: where do I look?  ("Simon Riggs", )
                      Re: User concurrency thresholding: where do I look?  (Tom Lane, )
                       Re: User concurrency thresholding: where do I look?  ("Simon Riggs", )
                      Re: User concurrency thresholding: where do I look?  ("Simon Riggs", )
                       Re: User concurrency thresholding: where do I look?  (Tom Lane, )
                        Re: User concurrency thresholding: where do I look?  ("Simon Riggs", )
                        Re: User concurrency thresholding: where do I look?  ("Jignesh K. Shah", )
                         Re: User concurrency thresholding: where do I look?  (Tom Lane, )
                          Re: User concurrency thresholding: where do I look?  ("Jignesh K. Shah", )
                           Re: User concurrency thresholding: where do I look?  (Tom Lane, )
                            Re: User concurrency thresholding: where do I look?  ("Jignesh K. Shah", )
                             Re: User concurrency thresholding: where do I look?  (Tom Lane, )
                              Re: User concurrency thresholding: where do I look?  (Robert Lor, )
                             Re: User concurrency thresholding: where do I look?  ("Simon Riggs", )
                              Re: User concurrency thresholding: where do I look?  ("Jignesh K. Shah", )
                               Re: User concurrency thresholding: where do I look?  ("Simon Riggs", )
                                Re: User concurrency thresholding: where do I look?  ("Jignesh K. Shah", )
                                 Re: User concurrency thresholding: where do I look?  (Alvaro Herrera, )
                                  Re: User concurrency thresholding: where do I look?  ("Simon Riggs", )
                                 Re: User concurrency thresholding: where do I look?  ("Simon Riggs", )
                                  Re: User concurrency thresholding: where do I look?  ("Jignesh K. Shah", )
                                  Re: User concurrency thresholding: where do I look?  ("Jignesh K. Shah", )
                                   Re: User concurrency thresholding: where do I look?  ("Jignesh K. Shah", )
                                    Re: User concurrency thresholding: where do I look?  ("Jignesh K. Shah", )
                                  Re: User concurrency thresholding: where do I look?  (Josh Berkus, )
                                   Re: User concurrency thresholding: where do I look?  ("Jignesh K. Shah", )
                              CLOG Patch  ("Jignesh K. Shah", )
                               Re: CLOG Patch  ("Simon Riggs", )
                                Re: CLOG Patch  ("Jignesh K. Shah", )
                                 Re: CLOG Patch  ("Simon Riggs", )
                           Re: User concurrency thresholding: where do I look?  ("Simon Riggs", )
       Re: User concurrency thresholding: where do I look?  (Greg Smith, )
        Re: User concurrency thresholding: where do I look?  (Josh Berkus, )
     Re: User concurrency thresholding: where do I look?  ("Joshua D. Drake", )
    Re: User concurrency thresholding: where do I look?  (Gregory Stark, )
 Re: User concurrency thresholding: where do I look?  (Greg Smith, )

David Boreham <> writes:
> Tom Lane wrote:
>> Having malloc/free use
>> an internal mutex is necessary in multi-threaded programs, but the
>> backend isn't multi-threaded.

> Hmm...confused. I'm not following why then there is contention for the
> mutex.

There isn't any contention for that mutex; Jignesh's results merely show
that it was taken and released a lot of times.

            regards, tom lane


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