Re: Proposal of tunable fix for scalability of 8.4

From: Kevin Grittner
Subject: Re: Proposal of tunable fix for scalability of 8.4
Date: ,
Msg-id: 49BA5960.EE98.0025.0@wicourts.gov
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In response to: Re: Proposal of tunable fix for scalability of 8.4  (Tom Lane)
Responses: Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey)
Re: Proposal of tunable fix for scalability of 8.4  ()
List: pgsql-performance

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Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
 Re: Proposal of tunable fix for scalability of 8.4  ("Kevin Grittner", )
  Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
   Re: Proposal of tunable fix for scalability of 8.4  ("Kevin Grittner", )
  Re: Proposal of tunable fix for scalability of 8.4  (Tom Lane, )
   Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
    Re: Proposal of tunable fix for scalability of 8.4  (Simon Riggs, )
     Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
     Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
      Re: Proposal of tunable fix for scalability of 8.4  (Simon Riggs, )
       Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
        Re: Proposal of tunable fix for scalability of 8.4  (Simon Riggs, )
        Re: Proposal of tunable fix for scalability of 8.4  (Gregory Stark, )
         Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
          Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
  Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
   Re: Proposal of tunable fix for scalability of 8.4  (Tom Lane, )
    Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
     Re: Proposal of tunable fix for scalability of 8.4  (decibel, )
      Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
       Re: Proposal of tunable fix for scalability of 8.4  (Josh Berkus, )
    Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
     Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
      Re: Proposal of tunable fix for scalability of 8.4  ("Kevin Grittner", )
      Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
       Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
        Re: Proposal of tunable fix for scalability of 8.4  (Gregory Stark, )
         Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
          Re: Proposal of tunable fix for scalability of 8.4  (Gregory Stark, )
         Re: Proposal of tunable fix for scalability of 8.4  (decibel, )
        Re: Proposal of tunable fix for scalability of 8.4  (Gregory Stark, )
        Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
         Re: Proposal of tunable fix for scalability of 8.4  ("Kevin Grittner", )
          Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
           Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
         Re: Proposal of tunable fix for scalability of 8.4  ("Kevin Grittner", )
         Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
          Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
           Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
            Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
          Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
           Re: Proposal of tunable fix for scalability of 8.4  (decibel, )
            Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
             Re: Proposal of tunable fix for scalability of 8.4  (Gregory Stark, )
              Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
      Re: Proposal of tunable fix for scalability of 8.4  (Greg Smith, )
   Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
    Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
    Re: Proposal of tunable fix for scalability of 8.4  (Greg Smith, )
     Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
      Re: Proposal of tunable fix for scalability of 8.4  (Robert Haas, )
       Re: Proposal of tunable fix for scalability of 8.4  (Tom Lane, )
        Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
        Re: Proposal of tunable fix for scalability of 8.4  ("Kevin Grittner", )
         Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
         Re: Proposal of tunable fix for scalability of 8.4  (, )
          Re: Proposal of tunable fix for scalability of 8.4  ("Kevin Grittner", )
           Re: Proposal of tunable fix for scalability of 8.4  ("Kevin Grittner", )
            Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
        Re: Proposal of tunable fix for scalability of 8.4  (Heikki Linnakangas, )
         Re: Proposal of tunable fix for scalability of 8.4  (Tom Lane, )
          Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
          Re: Proposal of tunable fix for scalability of 8.4  (Simon Riggs, )
         Re: Proposal of tunable fix for scalability of 8.4  (Matthew Wakeling, )
          Re: Proposal of tunable fix for scalability of 8.4  (Simon Riggs, )
           Re: Proposal of tunable fix for scalability of 8.4  (Matthew Wakeling, )
            Re: Proposal of tunable fix for scalability of 8.4  (Simon Riggs, )
             Re: Proposal of tunable fix for scalability of 8.4  (Matthew Wakeling, )
             Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
              Re: Proposal of tunable fix for scalability of 8.4  (Matthew Wakeling, )
               Re: Proposal of tunable fix for scalability of 8.4  (Simon Riggs, )
           Re: Proposal of tunable fix for scalability of 8.4  (Tom Lane, )
            Re: Proposal of tunable fix for scalability of 8.4  (Simon Riggs, )
           Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
            Re: Proposal of tunable fix for scalability of 8.4  (Matthew Wakeling, )
             Re: Proposal of tunable fix for scalability of 8.4  (Tom Lane, )
             Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
             Re: Proposal of tunable fix for scalability of 8.4  (Simon Riggs, )
          Re: Proposal of tunable fix for scalability of 8.4  (Heikki Linnakangas, )
           Re: Proposal of tunable fix for scalability of 8.4  (Matthew Wakeling, )
       Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
        Re: Proposal of tunable fix for scalability of 8.4  (Robert Haas, )
         Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
          Re: Proposal of tunable fix for scalability of 8.4  (Robert Haas, )
           Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
            Re: Proposal of tunable fix for scalability of 8.4  (Robert Haas, )
             Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
              Re: Proposal of tunable fix for scalability of 8.4  (Alvaro Herrera, )
               Re: Proposal of tunable fix for scalability of 8.4  (Alvaro Herrera, )
                Re: Proposal of tunable fix for scalability of 8.4  (Alvaro Herrera, )
                 Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
                  Re: Proposal of tunable fix for scalability of 8.4  (Robert Haas, )
                   Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
           Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
         Re: Proposal of tunable fix for scalability of 8.4  (Bruce Momjian, )
          Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
           Re: Proposal of tunable fix for scalability of 8.4  (Bruce Momjian, )
         Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
      Re: Proposal of tunable fix for scalability of 8.4  (Greg Smith, )
     8.4 Performance improvements: was Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
      Re: 8.4 Performance improvements: was Re: Proposal of tunable fix for scalability of 8.4  (Gregory Stark, )
      Re: 8.4 Performance improvements: was Re: Proposal of tunable fix for scalability of 8.4  (Gregory Stark, )
       Re: 8.4 Performance improvements: was Re: Proposal of tunable fix for scalability of 8.4  (Alan Stange, )
        Re: 8.4 Performance improvements: was Re: Proposal of tunable fix for scalability of 8.4  (Tom Lane, )
         Re: 8.4 Performance improvements: was Re: Proposal of tunable fix for scalability of 8.4  (Gregory Stark, )
          Re: 8.4 Performance improvements: was Re: Proposal of tunable fix for scalability of 8.4  (Tom Lane, )
           Re: 8.4 Performance improvements: was Re: Proposal of tunable fix for scalability of 8.4  (Robert Haas, )
            Re: 8.4 Performance improvements: was Re: Proposal of tunable fix for scalability of 8.4  (Gregory Stark, )
            Re: 8.4 Performance improvements: was Re: Proposal of tunable fix for scalability of 8.4  (Tom Lane, )
           Re: 8.4 Performance improvements: was Re: Proposal of tunable fix for scalability of 8.4  (Bruce Momjian, )
            Re: 8.4 Performance improvements: was Re: Proposal of tunable fix for scalability of 8.4  (Bruce Momjian, )
      Re: 8.4 Performance improvements: was Re: Proposal of tunable fix for scalability of 8.4  (Greg Smith, )
   Re: Proposal of tunable fix for scalability of 8.4  ("Kevin Grittner", )
    Re: Proposal of tunable fix for scalability of 8.4  (Grzegorz Jaśkiewicz, )
     Re: Proposal of tunable fix for scalability of 8.4  ("Kevin Grittner", )
      Re: Proposal of tunable fix for scalability of 8.4  (Ron, )
     Re: Proposal of tunable fix for scalability of 8.4  (Gregory Stark, )
      Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
    Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
     Re: Proposal of tunable fix for scalability of 8.4  (Tom Lane, )
      Re: Proposal of tunable fix for scalability of 8.4  (Alvaro Herrera, )
       Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
        Re: Proposal of tunable fix for scalability of 8.4  (decibel, )
      Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
    Re: Proposal of tunable fix for scalability of 8.4  (Tom Lane, )
     Re: Proposal of tunable fix for scalability of 8.4  (Scott Carey, )
    Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )
 Re: Proposal of tunable fix for scalability of 8.4  (Simon Riggs, )
  Re: Proposal of tunable fix for scalability of 8.4  ("Jignesh K. Shah", )

Tom Lane <> wrote:
> Robert Haas <> writes:
>> I think that changing the locking behavior is attacking the problem
>> at the wrong level anyway.
>
> Right.  By the time a patch here could have any effect, you've
> already lost the game --- having to deschedule and reschedule a
> process is a large cost compared to the typical lock hold time for
> most LWLocks.  So it would be better to look at how to avoid
> blocking in the first place.

That's what motivated my request for a profile of the "80 clients with
zero wait" case.  If all data access is in RAM, why can't 80 processes
keep 64 threads (on 8 processors) busy?  Does anybody else think
that's an interesting question, or am I off in left field here?

-Kevin


pgsql-performance by date:

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Date:
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From: Gregory Stark
Date:
Subject: Re: 8.4 Performance improvements: was Re: Proposal of tunable fix for scalability of 8.4