Re: tuplestore potential performance problem

Hitoshi Harada wrote:
> 2009/1/15 Bruce Momjian <bruce@momjian.us>:
> >
> > Has this been addressed?
> 
> It is mentioned at
> 
> http://archives.postgresql.org/pgsql-hackers/2008-12/msg01849.php
> 
> * Look at tuplestore performance issues. The tuplestore_in_memory()
> thing is just a band-aid, we ought to try to solve it properly.
> tuplestore_advance seems like a weak spot as well.
> 
> but not solved yet. It seems to me that to solve this the tuplestore's
> inside design should be changed much. In-file state doesn't use memory
> any more but it should be re-used for writing buffer, whereas the
> current desgin uses BufFile to do it, which causes tell/seek overhead
> for repeated put/get operation. And this is not for 8.4, I guess.

Oh, I see it is already on the TODO list;  great.  I have added
reference URL to the TODO.

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
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