On Fri, Dec 14, 2012 at 3:43 PM, S L <sol.leder...@gmail.com> wrote: > Does anyone have an idea why a query that takes solr just half a second (500 > ms) to execute would take 3 seconds to transfer the data?
Normally this is due to slow reading of the stored fields (i.e. slow disk IO). For scalability, we don't read all of the stored fields for the whole list into memory before starting to send the results, but stream them back instead. If that portion of the index isn't in the operating system cache, it's a disk seek per document (and that's not accounted for in the QTime since we've streamed that back already). Also possible is slowness on the client side - not reading fast enough for some reason. 3 seconds is a long time - how many documents were being returned (i.e. how many possible disk seeks)? The other random element thrown in sometimes are big random GC pauses. -Yonik http://lucidworks.com
