max_delay in async_sgd

[sunghlin]

Hi

Can we change the consistency condition in async_sgd model? I see you defined the max_delay, but never use it.

Thanks,

[mli]

the current version didn't implemented the bounded delay consistency for asynchronous sgd. i tested the bounded version, but didn't see any benefits if using a very large dataset, and it makes the semantic a little strange.

the batch algorithm, darlin, has the bounded delay implementation