Re: BLOB/BFILE Performance

From: D Rolfe <dwrolfeFRUITBAT_at_orindasoft.com>
Date: Mon, 10 Jan 2005 16:11:27 +0000
Message-ID: <JQxEd.45348$Z14.23979@news.indigo.ie>

DA Morgan wrote:

> SiY wrote:
> 

>> Hi,
>>
>> We have an application that requires the storage of approx 1/4 million
>> images. They consist of thumbnails (~2k) and larger images (~100k).
>>
>> We're planning on storing the thumbnails in the database (BLOB) and
>> the larger images outside (BFILES).
>>
>> They will be accessed by Java code using JDBC.
>>
>> I just wondered if there were any performance statistics around for
>> using BLOBS/BFILES on that number of images?
>>
>> Cheers
>> Si

> 
> 
> Why store any outside the database. And if you choose to do so what
> does the size have to do with it?

Storing inside the DB is the best option but you'll need to consider how often the images will be accessed. Returning BLOBS consumes significant resources and can easily swamp your hardware. You should try doing some tests and see how many thumbnails you can return per minute compared to what you expect to see traffic-wise. You should also consider that some BLOBs will be much more popular than others. I have seen a scenario where one image was being retrieved over and over again, using 25% of the DB server. My advice would be structure your app so that the BLOB can be retrieved from a dedicated web server that can perform crude caching if demand justfies it. That way you have a way out of the problem if you hit it.

David Rolfe
Orinda Software
Dublin Ireland

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Orinda Software make OrindaBuild, which writes DB access code for Oracle. www.orindabuild.com Received on Mon Jan 10 2005 - 10:11:27 CST