From: SPMLINGAM <spmlingam@gmail.com>
To: pgsql-performance@postgresql.org
Subject: postgresql performance
Date: Wed, 5 Mar 2008 02:27:08 -0800 (PST)
Message-ID: <15847165.post@talk.nabble.com> (raw)
Dear Friends,
I have a table with 50 lakhs records, the table has more then 10
fields, i have primary key, i have select query with count(*) without any
condition, it takes 17 seconds.
I have another one query which will do joins with other small tables, it
takes 47 seconds to give output, the result has 2 lakhs records. the
indexing is not used. I have created one index with one field ( which i
used in this query, the field value has duplicates also ).
Now the cpu usage is 4.4%, and waiting for io process .
i have checked the above in the top command.
If i delete that index, then it works fine, now the cpu usage takes more
then 70%, and waiting shows less then 30%.
Can Anyone explain, Why postgres behaves like this.
--
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To: pgsql-performance@postgresql.org
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Subject: Re: postgresql performance
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