Thanks, very helpful Rob, I'll watch for that. On Tue, Nov 25, 2014 at 11:45 AM, Robert Coli <rc...@eventbrite.com> wrote:
> On Tue, Nov 25, 2014 at 10:45 AM, Dan Kinder <dkin...@turnitin.com> wrote: > >> To be clear, I expect this range query to take a long time and perform >> relatively heavy I/O. What I expected Cassandra to do was use auto-paging ( >> https://issues.apache.org/jira/browse/CASSANDRA-4415, >> http://stackoverflow.com/questions/17664438/iterating-through-cassandra-wide-row-with-cql3) >> so that we aren't literally pulling the entire thing in. Am I >> misunderstanding this use case? Could you clarify why exactly it would slow >> way down? It seems like with each read it should be doing a simple range >> read from one or two sstables. >> > > If you're paging through a single partition, that's likely to be fine. > When you said "range reads ... over rows" my impression was you were > talking about attempting to page through millions of partitions. > > With that confusion cleared up, the likely explanation for lack of > availability in your case is heap pressure/GC time. Look for GCs around > that time. Also, if you're using authentication, make sure that your > authentication keyspace has a replication factor greater than 1. > > =Rob > > > -- Dan Kinder Senior Software Engineer Turnitin – www.turnitin.com dkin...@turnitin.com
