Limitation in retrieving rows from a mongodb from ruby code

Question

I have a code which gets all the records from a collection of a mongodb and then it performs some computations.

My program takes too much time as the "coll_id.find().each do |eachitem|......." returns only 300 records at an instant.

If I place a counter inside the loop and check it prints 300 records and then sleeps for around 3 to 4 seconds before printing the counter value for next set of 300 records..

coll_id.find().each do |eachcollectionitem|
    puts "counter value for record " + counter.to_s
    counter=counter +1 
            ---- My computations here ----- 
    end

Is this a limitation of ruby-mongodb api or some configurations needs to be done so that the code can get access to all the records at one instant.

score 0 · Answer 1 · answered Jan 26 '11 at 17:36

How large are your documents? It's possible that the deseriaization is taking a long time. Are you using the C extensions (bson_ext)?

You might want to try passing a logger when you connect. That could help sort our what's going on. Alternatively, can you paste in the MongoDB log? What's happening there during the pause?

Limitation in retrieving rows from a mongodb from ruby code

1 Answers1