On 21 September 2013 09:19, Sandy Ryza <sandy.r...@cloudera.com> wrote:
> I don't believe there is any reason scheduling decisions need to be coupled > with NodeManager heartbeats. It doesn't sidestep any race conditions > because a NodeManager could die immediately after heartbeating. > > historically its been done for scale: you don't need the JT reaching out to 4K TT's just to give them work to do, instead let them connect in anyway and get work that way. And once they start reporting in completion then they can get given more work. It's very biased towards "worker nodes talk to the master" over "master approaches workers" -- CONFIDENTIALITY NOTICE NOTICE: This message is intended for the use of the individual or entity to which it is addressed and may contain information that is confidential, privileged and exempt from disclosure under applicable law. If the reader of this message is not the intended recipient, you are hereby notified that any printing, copying, dissemination, distribution, disclosure or forwarding of this communication is strictly prohibited. If you have received this communication in error, please contact the sender immediately and delete it from your system. Thank You.