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From Robert Buck <>
Subject Re: Newbie: Locality of Reference in Couch
Date Thu, 27 May 2010 10:16:00 GMT
On Wed, May 26, 2010 at 9:01 PM, Randall Leeds <> wrote:
> On Wed, May 26, 2010 at 15:39, J Chris Anderson <> wrote:
>> On May 26, 2010, at 1:53 PM, Robert Buck wrote:
>>> Hi Folks,
>>> Thank you for kindly answering my last round of questions. Here is
>>> another question related to Couch:
>>> What sort of locality of reference exists in Couch with respect to
>>> retrieval of state ? Is locality of reference solely at the document
>>> level, or is locality of reference also exhibited elsewhere that
>>> developers can take advantage of ?
>> Hmm, I'm not sure what you mean by locality of reference (I know it in the context
of performance optimizations)
> Same.
> If you're using it this way, I guess the best answer is that documents
> might be very sparsely spread out across the disk in a large database
> that has not been compacted for a long time. Documents updated around
> the same time might be closer to the tail of the file. We really rely
> on the filesystem cache to make this something we can forget about.
> Does that answer anything at all?

That's good, that confirms what I have read, just wanted to verify.
Some database technologies allow you to "group" data more closely
together, some call this a container, others call it a segment. From
what I read Couch apparently has no such feature.

Thanks so much for your help.

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