Обсуждение: Why postgresql 8.3.5 created temporary files of size less then work_mem on disk ?

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Why postgresql 8.3.5 created temporary files of size less then work_mem on disk ?

От
"Yves D'Astous"
Дата:
Hello,

On a test postgresql server I have set work_mem to 200MB, and I have
stop/start postgressql.
I have also enable the  "log_temp_files = 0"

After restarting my server and executing some sql statements I see in
the postgres log:

LOG:  temporary file: path "base/pgsql_tmp/pgsql_tmp6655.10", size 122869324

So in what case temporary file of size less then work_mem are created on
disk ?


Yves D'Astous

Re: Why postgresql 8.3.5 created temporary files of size less then work_mem on disk ?

От
Michael Monnerie
Дата:
On Mittwoch 06 Mai 2009 Yves D'Astous wrote:
> So in what case temporary file of size less then work_mem are created
> on disk ?

I'd say when you have a complex query needing 5x 100MB for sorts, which
might be the case. But I'm no expert.

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