Hi Aimee, Thank you for your prompt reply. Best regards, Yu On Oct 12, 2012, at 9:55 AM, Aimee Cheng <chengsj....@gmail.com> wrote:
> I can answer your second question: no. In current S4 piper, when there are no > standby nodes, if one node crushes, the remaining nodes will not pick up the > task and still focus on their own tasks. > > -Aimee > > On Oct 12, 2012, at 9:36 AM, Frank Zheng wrote: > >> Hi, >> >> Thanks for your reply. >> So the dynamic load balancing is not implemented yet, right? >> In case of static load balancing, if there are two working PE node without >> any standby nodes, >> when one fails, does the workload for the remaining working PE increase? >> >> Besides, can zeno prototype do dynamic load balancing? >> >> Thanks. >> >> On Thu, Oct 11, 2012 at 7:00 PM, Matthieu Morel <mmo...@apache.org> wrote: >> On 10/11/12 12:35 PM, Daniel Gómez Ferro wrote: >> >> >> On Thu Oct 11 05:52:01 2012, Frank Zheng wrote: >> Hi All, >> >> I want to figure out the mechanism of load balancing in S4. >> In the paper and web site, it says ZooKeeper takes this >> responsibility, but the description is not very clear. >> I want to figure out that how ZooKeeper does load balancing. >> For example, if there are two working PE nodes, and 120 messages per >> second. The adapter distributes these messages evenly, 60 per PE node, >> right? >> When one PE node is added into the cluster, does it mean ZooKeeper >> balances the messages, 40 per PE node? >> And how does ZooKeeper decide which message to be distributed to which >> node? >> >> Hi, >> >> Currently load balancing is static. When you define your cluster you >> specify the number of tasks (say, 2) which won't change for this >> cluster. If you have more than 2 nodes, the rest will be backup nodes. >> In case one of the serving nodes fails, a backup node will pick up the >> orphaned task and start serving requests, but the load will always be >> spread among the 2 tasks that you defined at the beginning. >> >> Having dynamic load balancing would be really cool, but I don't know if >> there are currently any efforts in that direction. >> >> There is the zeno prototype https://github.com/s4/zeno , which is actually >> independent of S4. It also relies on ZooKeeper for metadata about partitions. >> >> Matthieu >> >> >> >> -- >> Sincerely, >> Zheng Yu >> Mobile: (852) 60670059 >> Email: bearzheng2...@gmail.com >> >> >> >
