One of the most significant changes was adding support for multiple backends. You can now use Active Record, MongoMapper, or DataMapper as backends for your job queue. See the README for more info.
The Active Record backend in delayed_job 2.0 is much faster (6x in the benchmarks I ran), primarily due to reversing the priority column and adding an index. Here are benchmarks for running 10,000 simple jobs on my laptop:
user system total real delayed_job 1.8.5 195.670000 14.020000 209.690000 (230.887172) delayed_job 2.0 36.200000 0.940000 37.140000 ( 39.959233)
While we’re looking at benchmarks, here is how the current backends compare:
user system total real active_record 36.200000 0.940000 37.140000 ( 39.959233) mongo_mapper 69.270000 3.220000 72.490000 ( 90.783220) data_mapper 255.620000 2.880000 258.500000 (275.550383)
I have not done anything to optimize the mongo_mapper or data_mapper backend, so performance patches would be appreciated.
To take full advantage of the Active Record performance improvements, you’ll want to add an index:
The only other issue that most people will run into is that all of the configuration options have been moved to
Delayed::Worker. Here’s how to change the options now:
Feel free to post any comments or questions on the mailing list.