Re: Performance problems testing with Spamassassin 3.1.0

From: Matthew Schumacher
Subject: Re: Performance problems testing with Spamassassin 3.1.0
Date: ,
Msg-id: 42F23FB6.5010405@aptalaska.net
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In response to: Re: Performance problems testing with Spamassassin 3.1.0  (Tom Lane)
Responses: Re: Performance problems testing with Spamassassin 3.1.0  (Matthew Schumacher)
List: pgsql-performance

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Performance problems testing with Spamassassin 3.1.0 Bayes module.  (Matthew Schumacher, )
 Re: Performance problems testing with Spamassassin 3.1.0 Bayes module.  (Josh Berkus, )
  Re: Performance problems testing with Spamassassin 3.1.0  (Matthew Schumacher, )
   Re: Performance problems testing with Spamassassin 3.1.0 Bayes module.  (Josh Berkus, )
    Re: Performance problems testing with Spamassassin 3.1.0  (Matthew Schumacher, )
   Re: Performance problems testing with Spamassassin 3.1.0  (Dennis Bjorklund, )
    Re: Performance problems testing with Spamassassin 3.1.0  (Josh Berkus, )
     Re: Performance problems testing with Spamassassin 3.1.0  (John Arbash Meinel, )
 Re: Performance problems testing with Spamassassin 3.1.0 Bayes module.  (Tom Lane, )
  Re: Performance problems testing with Spamassassin  ("Luke Lonergan", )
 Re: Performance problems testing with Spamassassin 3.1.0  (Karim Nassar, )
  Re: Performance problems testing with Spamassassin 3.1.0  (Matthew Schumacher, )
   Re: Performance problems testing with Spamassassin 3.1.0  (Gavin Sherry, )
    Re: Performance problems testing with Spamassassin 3.1.0  (Matthew Schumacher, )
     Re: Performance problems testing with Spamassassin 3.1.0  (Gavin Sherry, )
   Re: Performance problems testing with Spamassassin 3.1.0  (Andrew McMillan, )
    Re: Performance problems testing with Spamassassin 3.1.0  (Matthew Schumacher, )
     Re: Performance problems testing with Spamassassin 3.1.0  (PFC, )
     Re: Performance problems testing with Spamassassin 3.1.0  (Andrew McMillan, )
      Re: Performance problems testing with Spamassassin 3.1.0  (Matthew Schumacher, )
      Re: Performance problems testing with Spamassassin 3.1.0  (Tom Lane, )
       Re: Performance problems testing with Spamassassin 3.1.0  (Matthew Schumacher, )
        Re: Performance problems testing with Spamassassin 3.1.0  (Tom Lane, )
         Re: Performance problems testing with Spamassassin 3.1.0  (Matthew Schumacher, )
          Re: Performance problems testing with Spamassassin 3.1.0  (John Arbash Meinel, )
         Re: Performance problems testing with Spamassassin 3.1.0  (Michael Parker, )
          Re: Performance problems testing with Spamassassin 3.1.0  (Tom Lane, )
          Re: Performance problems testing with Spamassassin 3.1.0  (Tom Lane, )
           Re: Performance problems testing with Spamassassin 3.1.0  (Matthew Schumacher, )
         Re: Performance problems testing with Spamassassin 3.1.0  (Matthew Schumacher, )
          Re: Performance problems testing with Spamassassin 3.1.0  (PFC, )
           Re: Performance problems testing with Spamassassin 3.1.0  (Matthew Schumacher, )
            Re: Performance problems testing with Spamassassin 3.1.0  ("Jim C. Nasby", )
             Re: Performance problems testing with Spamassassin 3.1.0  (Michael Parker, )
              Re: Performance problems testing with Spamassassin 3.1.0  (Matthew Schumacher, )
               Re: Performance problems testing with Spamassassin 3.1.0  (PFC, )
               Re: Performance problems testing with Spamassassin 3.1.0  (John A Meinel, )
                Re: Performance problems testing with Spamassassin 3.1.0  (Matthew Schumacher, )
               Re: Performance problems testing with Spamassassin 3.1.0  (Tom Lane, )
                Re: Performance problems testing with Spamassassin 3.1.0  (John A Meinel, )
                 Re: Performance problems testing with Spamassassin 3.1.0  (Tom Lane, )
                Re: Performance problems testing with Spamassassin 3.1.0  (Matthew Schumacher, )
                 Re: Performance problems testing with Spamassassin 3.1.0  (Matthew Schumacher, )
                  Re: Performance problems testing with Spamassassin 3.1.0  (John A Meinel, )
                   Re: Performance problems testing with Spamassassin 3.1.0  (Matthew Schumacher, )
                    Re: Performance problems testing with Spamassassin 3.1.0  (John A Meinel, )
        Re: Performance problems testing with Spamassassin 3.1.0  (John Arbash Meinel, )
         Re: Performance problems testing with Spamassassin 3.1.0  (John Arbash Meinel, )
          Re: Performance problems testing with Spamassassin 3.1.0  (Matthew Schumacher, )
           Re: Performance problems testing with Spamassassin 3.1.0  ("Jim C. Nasby", )
            Re: Performance problems testing with Spamassassin 3.1.0  (Andreas Pflug, )
 Re: Performance problems testing with Spamassassin 3.1.0 Bayes module.  ("Merlin Moncure", )

Tom Lane wrote:

> I don't really see why you think that this path is going to lead to
> better performance than where you were before.  Manipulation of the
> temp table is never going to be free, and IN (sub-select) is always
> inherently not fast, and NOT IN (sub-select) is always inherently
> awful.  Throwing a pile of simple queries at the problem is not
> necessarily the wrong way ... especially when you are doing it in
> plpgsql, because you've already eliminated the overhead of network
> round trips and repeated planning of the queries.
>
>             regards, tom lane

The reason why I think this may be faster is because I would avoid
running an update on data that needs to be inserted which saves
searching though the table for a matching token.

Perhaps I should do the insert first, then drop those tokens from the
temp table, then do my updates in a loop.

I'll have to do some benchmarking...

schu


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From: John A Meinel
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Subject: Re: Performance problems testing with Spamassassin 3.1.0
From: Matthew Schumacher
Date:
Subject: Re: Performance problems testing with Spamassassin 3.1.0