Re: Is PostgreSQL for this? - Mailing list pgsql-general

From Ron Johnson
Subject Re: Is PostgreSQL for this?
Date
Msg-id 4592DE22.1020207@cox.net
Whole thread Raw
In response to Re: Is PostgreSQL for this?  (Richard Broersma Jr <rabroersma@yahoo.com>)
List pgsql-general
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On 12/27/06 11:59, Richard Broersma Jr wrote:
>> I'm looking for a database system for a SCADA system. The major
>>  probles I think it's on performance because the application
>> it's going to poll about 4k variables per second from hardware
>> and has to register the values on the procces table. I heard
>> that PostgreSQL provides a bulk loading mechanism called COPY,
>> which takes tab-delimited or CSV input from a file. Where COPY
>> can be used instead of hundreds or thousands of INSERTS, it can
>> cut execution time.
>
> I think Postgresql can do what you want provide you have the
> hardware that can support 4K + writes/second.  However, if you

As others have mentioned, DP variables are 8 bytes.  If metadata is
16 bytes, that's a total of (8+16)*4096 = 96KBps.

Trivial for even the slowest home-designed hard disks.

Let's then take the CPU.  A dual-core 2GHz Opteron has 4 gigacycles
per second.  That gives a dedicated machine 1 megacycle to handle
each variable per second.

I certainly think that's achievable...

- --
Ron Johnson, Jr.
Jefferson LA  USA

Is "common sense" really valid?
For example, it is "common sense" to white-power racists that
whites are superior to blacks, and that those with brown skins
are mud people.
However, that "common sense" is obviously wrong.
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