citi_bike_large failure on groupby #13916
Description
citi_bike_large.ipynb fails intermittently on this group-by block:
group_by_cols = ["Days","start station name"]
aggregates = {"bikes": ["count", 0, "all"]}
bpd = h2o.group_by(data, cols=group_by_cols, aggregates=aggregates)
bpd.show()
bpd.describe()
bpd.dim()
with:
04-23 18:45:08.419 172.16.2.175:56789 26571 # Session INFO: Method: POST , URI: /3/Rapids, route: /3/Rapids, parms: {ast=(= !pyff26abec-2831-45c0-b29f-cdde3d76a1da (GB %pyea2f2288-6474-46c8-b8df-de481f5b2cdf (llist #15 #4) (agg "count" #0 "all" "bikes")))}
04-23 18:45:09.574 172.16.2.175:56789 26571 # Session ERRR: java.lang.RuntimeException: water.DException$DistributedException: from /172.16.2.175:56789; by class water.rapids.ASTGroupBy$GBTask; class water.DException$DistributedException: from /172.16.2.175:56791; by class water.rapids.ASTGroupBy$GBTask; class java.lang.NullPointerException: null
java.lang.RuntimeException: water.DException$DistributedException: from /172.16.2.175:56789; by class water.rapids.ASTGroupBy$GBTask; class water.DException$DistributedException: from /172.16.2.175:56791; by class water.rapids.ASTGroupBy$GBTask; class java.lang.NullPointerException: null
at water.MRTask.getResult(MRTask.java:265)
at water.MRTask.doAll(MRTask.java:220)
at water.MRTask.doAll(MRTask.java:216)
at water.rapids.ASTGroupBy.apply(ASTGroupBy.java:82)
at water.rapids.AST.treeWalk(AST.java:49)
at water.rapids.AST.treeWalk(AST.java:83)
at water.rapids.Exec.exec(Exec.java:68)
at water.api.RapidsHandler.exec(RapidsHandler.java:34)
at sun.reflect.GeneratedMethodAccessor7.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at water.api.Handler.handle(Handler.java:57)
at water.api.RequestServer.handle(RequestServer.java:668)
at water.api.RequestServer.serve(RequestServer.java:604)
at water.NanoHTTPD$HTTPSession.run(NanoHTTPD.java:434)
at java.lang.Thread.run(Thread.java:745)
Caused by: water.DException$DistributedException: from /172.16.2.175:56789; by class water.rapids.ASTGroupBy$GBTask; class water.DException$DistributedException: from /172.16.2.175:56791; by class water.rapids.ASTGroupBy$GBTask; class java.lang.NullPointerException: null
at water.rapids.ASTGroupBy$GBTask.map(ASTGroupBy.java:215)
at water.MRTask.compute2(MRTask.java:415)
at water.MRTask.compute2(MRTask.java:374)
at water.MRTask.compute2(MRTask.java:374)
at water.MRTask.compute2(MRTask.java:374)
at water.MRTask.compute2(MRTask.java:374)
at water.H2O$H2OCountedCompleter.compute(H2O.java:672)
at jsr166y.CountedCompleter.exec(CountedCompleter.java:429)
at jsr166y.ForkJoinTask.doExec(ForkJoinTask.java:263)
at jsr166y.ForkJoinPool$WorkQueue.pollAndExecAll(ForkJoinPool.java:914)
at jsr166y.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:979)
at jsr166y.ForkJoinPool.runWorker(ForkJoinPool.java:1477)
at jsr166y.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:104)