Hello!
I have a problem with a view being slow, even though it’s indexed and cached
and so on. I have database of books (–120,000 documents) and a map/reduce
function that counts how many books there are per author. I’m then calling the
view with ?group=true to get the list. I’m neither emitting nor outputting any
actual documents, only the counts. This results in an output of about 78,000
key/value pairs that look like the following: {"key":"Albert Kapr","value":3}.
Now, even when the view is indexed and cached, it still takes 60 seconds to
receive the output, using PHP’s cURL functions, the browser, whatever I’ve
tried. Getting the same output served from a static file takes only a fraction
of a second.
When I set limit=100, it’s basically instantaneous. I want to sort the output
by value though, so I can’t really limit it or use ranges. Trying it with about
7,000 books, the request takes about 5 seconds, so it seems to be linear to the
number of lines being output?
I’m using CouchDB 0.10.1 (the one that’s in homebrew) on a 2006 MacBook Pro.
Am I doing anything wrong, or should this really take so long? I wasn’t able to
find any information about this—only about indexing being slow, but that
doesn’t seem to be my problem.
Maybe I should also mention that I’m an interaction design student who used to
be a front-end dev, but not a ‘real’ programmer.
Thanks for any help!
Best,
Julian
For reference, the map function:
function (doc)
{
if (doc.author) {
for (i = 0; i < doc.author.length; i++) {
emit(doc.author[i], 1);
}
} else {
emit(null, 1);
}
}
The reduce function:
function (keys, values, rereduce)
{
return sum(values);
}
Some sample output:
{"rows":[
{"key":null,"value":1542},
{"key":"... Hans Arp ... /Konzept: Hans Christian Tavel .../","value":1},
---more rows---
{"key":"Zwi Erich Kurzweil","value":1}
]}
