"Map/reduce operations aren’t exactly blazing fast, and are single-threaded (though they will parallelize over shards)."
This sounds extremely pointless with it being single-threaded, but whatever.
Its single-threaded nature for map/reduce is its biggest liability in my opintion. It will apparently be fixed in the next version (https://jira.mongodb.org/browse/SERVER-4258)
Right now, large map/reduce operations just bring the thing to its knees. So we just don't map/reduce with it. The query features are really quite nice, and we do the rest in hypertable.
Right now, large map/reduce operations just bring the thing to its knees. So we just don't map/reduce with it. The query features are really quite nice, and we do the rest in hypertable.