Hello! What kind of migrations are you expecting? I guess you could add or remove fields just by doing rolling upgrade (restart nodes to V2 one by one until no nodes with V1 are left).
Trying to rename fields is not recommended and changing fields' type is not supported. Regards, -- Ilya Kasnacheev ср, 29 мая 2019 г. в 15:54, Scott Cote <sc...@etcc.com>: > Ivan, > > I think that you gave me the right answer and confirmed my suspicion - > that peer class loading is only for just an executable and not data. > > Can I assist by helping edit the documentation on the Apache Ignite site > to add clarity on when a jar is needed in the lib folder? > > Also - I'll have to come up with a plan to flush out of date java data > classes, or maybe you guys have some techniques that allow for online > migration of v1 of a java data class to v2 of a java data class without > having to shutdown the whole set of vm's. > > Our system is pretty simple. > > > We use the cache's. > > Not the streamers. > > Not the callables ... > > It’s a big fantastic cache 😊 > > (With some stuff that I built on top of it - like a priority queue > framework) > > SCott > > -----Original Message----- > From: Павлухин Иван <vololo...@gmail.com> > Sent: Wednesday, May 29, 2019 1:16 AM > To: user@ignite.apache.org > Subject: Re: FW: class loading, peer class loading, jars, fun times in > ignite > > Hi Scott, > > As far as I know, peer class loading does not work for data classes (which > are stored in a cache). It works for tasks sended for execution using > IgniteCompute. > > It is only a partial answer. Could you describe your use case in more > details? > > вт, 28 мая 2019 г. в 23:35, Scott Cote <sc...@etcc.com>: > > > > Whoops – sent to the wrong list … > > > > > > > > From: Scott Cote > > Sent: Tuesday, May 28, 2019 1:04 PM > > To: d...@ignite.apache.org > > Subject: class loading, peer class loading, jars, fun times in ignite > > > > > > > > I am fairly certain that I don’t know how to use peer class loading > properly. > > > > > > > > Am using Apache Ignite 2.7. If I have a node running on 192.168.1.2 > with a peer class loading enabled, and I start up a second node – > 192.168.1.3, client mode enabled and peer class loading enabled, then I > expected the following: > > > > > > > > Running the snippet (based on > https://apacheignite.readme.io/docs/getting-started#section-first-ignite-data-grid-application > ) on the client (192.168.1.3): > > > > > > > > try (Ignite ignite = > > Ignition.start("examples/config/example-ignite.xml")) { > > > > IgniteCache<Integer, MyWrapperOfString> cache = > > ignite.getOrCreateCache("myCacheName"); > > > > > > > > // Store keys in cache (values will end up on different cache nodes). > > > > for (int i = 0; i < 10; i++) > > > > cache.put(i,new MyWrapperOfString( Integer.toString(i))); > > > > > > > > for (int i = 0; i < 10; i++) > > > > System.out.println("Got [key=" + i + ", val=" + cache.get(i) + > > ']'); > > > > } > > > > > > > > > > > > Would cause the cache of “MyWrapperOfString” instances to be available > on 192.168.1.2 and on 192.168.1.3 . Also be able to observe the cache > using visor, etc …. > > > > > > > > However – I instead get an error that the class “MyWrapperOfString” is > not available on 192.168.1.2. Now if I take the jar that the class is > packed, and place it in the lib folder, all is happy. > > > > > > > > Should I have to do this? > > > > If yes – how do I update the jar if I have a cluster of nodes doing > this? Do I have to shutdown the entire cluster in order to not have class > loader problems? > > > > I thought the peer class loading is supposed to solve this problem. > > > > > > > > I think it would be VERY INSTRUCTIVE for the snippet that I anchored to > not use a standard java library cache object, but to demonstrate the need > to package value object into a jar and stuff it into the lib folder (If > this is what is expected). Running lambdas that use basic java > primitives is cool, but is this the normal? > > > > > > > > Switching up …. Is there interest in me creating class loader that would > load java classes into the vm that could be incorporated into ignite? So > instead of reading a jar, you load the class bytes into a cache . You want > to hot load a new class? Fine ! pump into the DISTRIBUTED_CLASS_PATH_CACHE > . > > > > > > > > Cheers. > > > > > > > > SCott > > > > > > > > -- > Best regards, > Ivan Pavlukhin >
