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From Cortland Klein ...@pixelcort.com>
Subject Re: Updating views on save
Date Mon, 28 Apr 2008 06:49:32 GMT
Not sure why your views are timing out, but from my current  
understanding views are incrementally updated with modifications but  
only incrementally updated on a call to that view.

One hypothesis is that after the thousands of inserts the next view  
call is taking a long time doing the incremental updates to the view  
since the last time it was called.

Are you using the javascript spodermonkey viewserver(default) or  
another one? Check the complexity of the view and possibly minimize  
the view's complexity.

As a final thought iirc when querying a view in a design document, all  
views in that designdocument are called. Is it possible you might have  
unrelated views in the same design document?

I'm not sure, but I think the pattern here is you put views most  
likely to be called near to each other in the design document, say  
blog summaries view followed by full content view, and have less  
related views in a different design document, say for a list of  
authors or a tag list.

Hope this helps.

Cortland Klein <me@pixelcort.com> +1 408 506 9791
http://pixelcort.com/

Sent from my iPhone

On Apr 27, 2008, at 4:04 PM, Guby <guby.mail@gmail.com> wrote:

> Hello dear Couchers
>
> I understand that the views are indexed the first time they are  
> accessed and as far as I know there is no way to turn on view  
> updating on document save. I really don't understand the reasoning  
> behind this behavior. The advantage of the pre-populated/indexed  
> views are that they are blazingly fast to query and access, but that  
> advantage disappears when the first request after a document update  
> has to regenerate the view first!
>
> I am currently building a web app where the background processes  
> perform a lot of writes to the database. The time it takes to write  
> a document is not critical for me. What is critical though is the  
> time it takes to load web pages for the end user that require  
> content from the database.
> In some situations the background processes add thousands of  
> documents to the database within a short period of time, and when  
> the user tries to access a page after such an update the view  
> querying sometimes takes minutes and as a consequence of that the  
> browser times out... Not a recipe for happy customers...
>
> The only solution I can see at the moment is to create a worker that  
> queries the database whenever it is told that there has been a  
> document update, but that seems really stupid and unnecessary. And  
> in my case, running on a smallish VPS, a big waste of resources  
> having an extra working doing something the database itself could  
> just as well have done. It also requires a lot of extra coding  
> notifying the worker whenever I update or create a document  
> throughout my app.
>
> I am sure you have reasons for having implemented the views the way  
> you have, but I would be really interested to hear why it has been  
> done this way!
>
> My wishes are for an optional updating of views on save feature! In  
> some cases that might regenerate a view several times without it  
> actually being accessed in between, but that is a tradeoff I can  
> live with, slow views on the other hand is something I can not!
>
> All the best
> Sebastian

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