Ah, very good. Thanks for that link (I don't think I had seen that page before). A couple of questions about some of those 2.2 details: 1) Is Hazelcast no longer used at all or are Hazelcast queues just not used for intra-node communications? 2) Is client-side load balancing supported on the node.js driver (orientjs)? 3) In a distributed application (say, 3 ODB nodes) where multiple end-client requests need to access and modify the same data (something like a session object in a multi-server web application), I'm concerned about consistency (i.e. end-client A updates a record when connected to node 1, then end-client B queries that record when connected to node 2, but gets stale data from before end-client A's update). I realize this is a common problem for any distributed system, but I don't fully understand ODB's consistency "guarantees". Assuming that writeQuorum is "majority", if node 1 and 2 both successfully commit the update, it is my understanding that end-client B will get the updated data (just as if it had connected to node 1), but what if node 2 fails the update (but node 3 successfully commits, thereby satisfying the writeQuorum)? What other scenarios should I watch out for (I'm keying on the comment about consistency mentioned in relation to per-request round-robin, but not per-connection round-robin, and I'm not sure why this would be particularly different)? Also, if the update is to just one record, is an explicit transaction of any kind needed here?
On Sunday, May 8, 2016 at 4:55:26 AM UTC-5, l.garulli wrote: > > In v2.2 is not supported anymore in the meaning that hotAlignment is > ALWAYS on, look at: > https://github.com/orientechnologies/orientdb-docs/blob/master/Release-2.2.0.md#distributed > . > > Best Regards, > > Luca Garulli > Founder & CEO > OrientDB <http://orientdb.com/> > > > On 7 May 2016 at 17:35, Eric24 <[email protected] <javascript:>> wrote: > >> Is hotAlignment working now in 2.2? >> >> On Wednesday, April 29, 2015 at 2:02:07 AM UTC-5, l.garulli wrote: >>> >>> Hi, >>> Unfortunately hotAlignment is still not working, in the meaning that >>> cannot guarantee 100% consistency of database. >>> >>> We are working with Hazelcast team for a more efficient solution (more >>> reliable and much faster). This will be available in 2.2 (June 2015) or >>> lately 3.0 (summer 2015). >>> >>> Lvc@ >>> >>> >>> Best Regards, >>> >>> Luca Garulli >>> CEO at Orient Technologies LTD >>> the Company behind OrientDB >>> http://about.me/luca.garulli >>> >>> >>> On 28 April 2015 at 23:34, S. Monkey <[email protected]> wrote: >>> >>>> The documentation for distributed architecture ( >>>> http://orientdb.com/docs/last/Distributed-Architecture.html) states >>>> that hotAlignment should be set to false as true can lead to >>>> inconsistency. >>>> >>>> Is this still the case in version 2.0.X (2.0.8 specifically)? >>>> >>>> If so, what is the correct way to configure a distributed database? If >>>> autoDeploy is set to true then it appears that whenever starting a node >>>> that joins a distributed cluster, the database is automatically deployed, >>>> even if the node was previously a member of the cluster. For a large >>>> database this could be problematic, but it seems this would be necessary >>>> without a mechanism like hotAlignment. >>>> >>>> -- >>>> >>>> --- >>>> You received this message because you are subscribed to the Google >>>> Groups "OrientDB" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to [email protected]. >>>> For more options, visit https://groups.google.com/d/optout. >>>> >>> >>> -- >> >> --- >> You received this message because you are subscribed to the Google Groups >> "OrientDB" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] <javascript:>. >> For more options, visit https://groups.google.com/d/optout. >> > > -- --- You received this message because you are subscribed to the Google Groups "OrientDB" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
