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From "Chris Van Pelt" <>
Subject Re: Slooooow views
Date Wed, 07 Jan 2009 23:38:08 GMT
Ok, so I created a gist with the map, reduce, and a document:

The purpose of this view is to combine multiple judgments (the data
attribute of the doc) for a single unit_id.  The "fields
 attribute tells couch how to aggregate the data (averaging numbers,
choosing the most common item, etc.).

I do use group=true, along with skip and count when querying this
view.  I understand that skip can slow things down, but the request is
still slow when skip is 0.

Another strange thing is that even when I query one of my "count"
views (a simple sum() reduce step) I experience the same lag.  Could
this be because my count views are a part of the same design document?

Also are there better ways to debug this?  I've set my log level to
debug, but it doesn't give me details about where the time spent
processing is going, and I can only gauge response times to the


On Wed, Jan 7, 2009 at 3:12 PM, Chris Anderson <> wrote:
> On Wed, Jan 7, 2009 at 3:07 PM, Jeremy Wall <> wrote:
>> Maybe someone else could chime in on when you get the hit for reduction?
> Based on my use of log() in the reduce function, it looks like for
> each reduce query, the reduce function is run once, to obtain the
> final reduce value.
> When you run a group=true, or group_level reduce query, which returns
> values for many keys, you'll end up running the final reduction once
> per returned value. I think this could be optimized to avoid running
> final reduces if they've already been run for those key-ranges. I'm
> not sure how much work that would be.
> --
> Chris Anderson

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