Message-ID: <4F230185.8020203@enterprisedb.com>
Date: Fri, 27 Jan 2012 21:56:53 +0200
From: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>
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To: Jayashankar K B <Jayashankar.KB@lnties.com>
CC: Andy Colson <andy@squeakycode.net>,
	"pgsql-performance@postgresql.org" <pgsql-performance@postgresql.org>
Subject: Re: Postgress is taking lot of CPU on our embedded hardware.
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On 27.01.2012 20:30, Jayashankar K B wrote:
> Hi Heikki Linnakangas: We are using series of Insert statements to insert the records into database.
> Sending data in binary is not an option as the module that writes into DB has been finalized.
> We do not have control over that.

That certainly limits your options.

> Please let me know how we can proceed. On the net I couldn't get hold of any good example where Postgres has been used on limited Hardware system.

I don't think there's anything particular in postgres that would make it 
a poor choice on a small system, as far as CPU usage is concerned 
anyway. But inserting rows in a database is certainly slower than, say, 
writing them into a flat file.

At what rate are you doing the INSERTs? And how fast would they need to 
be? Remember that it's normal that while the INSERTs are running, 
postgres will use all the CPU it can to process them as fast as 
possible. So the question is, at what rate do they need to be processed 
to meet your target. Lowering the process priority with 'nice' might 
help too, to give the other important processes priority over postgres.

The easiest way to track down where the time is spent would be to run a 
profiler, if that's possible on your platform.

-- 
   Heikki Linnakangas
   EnterpriseDB   http://www.enterprisedb.com