Re: tuplestore potential performance problem - Mailing list pgsql-hackers

From Hitoshi Harada
Subject Re: tuplestore potential performance problem
Date
Msg-id e08cc0400901142129k283f37b1q63e7d8eb4a31aeb1@mail.gmail.com
Whole thread Raw
In response to Re: tuplestore potential performance problem  (Bruce Momjian <bruce@momjian.us>)
Responses Re: tuplestore potential performance problem  (Tom Lane <tgl@sss.pgh.pa.us>)
Re: tuplestore potential performance problem  (Bruce Momjian <bruce@momjian.us>)
List pgsql-hackers
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.


Regards,

-- 
Hitoshi Harada


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