After build another cube successfully, I recheck this bug and find the reason, thanks to all of you ...
2015-09-11 11:17 GMT+08:00 ShaoFeng Shi <[email protected]>: > If "rowkey_stats" wasn't found, Kylin should throw exception and exit, > instead of using 1 region silently; I'm going to change this, please let me > know if you don't agree. > > 2015-09-11 10:17 GMT+08:00 Yerui Sun <[email protected]>: > > > Hi, yu feng, > > Let me guess the reason of your problem. > > > > The num of reducers of converting hfile job depends on the region > > numbers of corresponding HTable. > > > > For now, all HTables were created with only one region, caused by the > > wrong path of rowkey_stats. I’ve opened a jira for this issue: > > https://issues.apache.org/jira/browse/KYLIN-968. The patch has been > > available last night. > > > > Here’s some clues to confirm my guessing: > > 1. You can find the corresponding HTable name in log, check its > regions, > > it should have only one region. > > 2. Check your kylin working directory on hdfs, there should be a path > > like ‘../kylin-null/../rowkey_stats'. > > 3. Grep your kylin.log in tomcat dir, you should find the log contains > > ‘no region split, HTable will be one region’. > > > > If you hit all the three clues, I think KYLIN-968 could resolve your > > problem. > > > > > > > 在 2015年9月11日，00:54，yu feng <[email protected]> 写道： > > > > > > OK, I find another problem(I am a problem maker, ^_^), today I buid > this > > > cube which has 15 dimensions(one Mandatory dimension, to hierarchy > > > dimension and others are normal dimension), I find cuboid files are > > 1.9TB, > > > in the step of converting cuboid to hfile it is too slow. I check the > log > > > of this job and find there are 9000+ mappers and only one reducer. > > > > > > I discard this job when our hadoop administrator tells me the node > witch > > > run this reducer is out of space of disk. I have to stop it, I am doubt > > > that why there are only one reducer(I do not check source code of this > > > job), By the way, my original data is only hundreds MB. I think this > > would > > > cause more problems if original is bigger or dimension is much more.. > > > > > > 2015-09-10 23:46 GMT+08:00 Luke Han <[email protected]>: > > > > > >> The 2.0 will not come recently, there are huge refactor and bunch of > new > > >> features, we have to make sure there are no critical bugs before > > release. > > >> > > >> The same function also available under v1.x branch, please stay tuned > > for > > >> update information for that. > > >> > > >> Thanks. > > >> > > >> > > >> Best Regards! > > >> --------------------- > > >> > > >> Luke Han > > >> > > >> On Thu, Sep 10, 2015 at 7:50 PM, yu feng <[email protected]> > wrote: > > >> > > >>> What good news ! I wish you can release the version as quickly as > > >>> possible, Today, I build a cube whose cuboid files is 1.9TB. If we > > merge > > >>> cube based on cuboid files, I think it will be very slowly.. > > >>> > > >>> 2015-09-10 19:34 GMT+08:00 Shi, Shaofeng <[email protected]>: > > >>> > > >>>> We have implemented the merge from HTable directly in Kylin 2.0, > which > > >>>> hasn’t been released/announced. > > >>>> > > >>>> On 9/10/15, 7:22 PM, "yu feng" <[email protected]> wrote: > > >>>> > > >>>>> I think kylin can finish merging just depend on tables on hbase, > This > > >>> will > > >>>>> make merging cubes more quickly, Isn't it ? > > >>>>> > > >>>>> 2015-09-10 19:16 GMT+08:00 yu feng <[email protected]>: > > >>>>> > > >>>>>> After check source code, I find you are right, cuboid files will > be > > >>> used > > >>>>>> while merging segments, But a new question comes, Why kylin merge > > >>>>>> segment > > >>>>>> just based on hfile, I can not find how to take hbase table as > input > > >>>>>> format > > >>>>>> of mapreduce job, But kylin take HFileOutputFormat as output > format > > >>>>>> while > > >>>>>> changing cuboid to hfile. > > >>>>>> > > >>>>>> From this, I find kylin will take more space for a cube actually , > > >> not > > >>>>>> only hfile but also cuboid files, the former are used for query > and > > >>> the > > >>>>>> latter are used for merge, and the capacity of cuboid files is > > >> bigger > > >>>>>> than > > >>>>>> hfiles. > > >>>>>> > > >>>>>> I think we could do some thing to optimize it... I want to know > your > > >>>>>> opinions about it . > > >>>>>> > > >>>>>> 2015-09-10 18:36 GMT+08:00 Yerui Sun <[email protected]>: > > >>>>>> > > >>>>>>> Hi, yu feng, > > >>>>>>> I’ve also noticed these files and opened a jira: > > >>>>>>> https://issues.apache.org/jira/browse/KYLIN-978, and I’ll post a > > >>> patch > > >>>>>>> tonight. > > >>>>>>> > > >>>>>>> Here’s my opinions on your three question, feel free to correct > > >> me: > > >>>>>>> > > >>>>>>> First, the data path of intermediate hive table should be > deleted > > >>>>>>> after > > >>>>>>> building, I agreed with that. > > >>>>>>> > > >>>>>>> Second, the cuboid files will be used for merge and will be > > >> deleted > > >>>>>>> when merging job completed, we need and must leave them on hdfs. > > >> The > > >>>>>>> fact_distint_columns should be deleted. In additionally, the path > > >> of > > >>>>>>> rowkey_stats and hfile > > >>>>>>> should also be deleted. > > >>>>>>> > > >>>>>>> Third, there’s no garbage collection steps if a job discard, > > >> maybe > > >>> we > > >>>>>>> need a patch for this. > > >>>>>>> > > >>>>>>> > > >>>>>>> Short answer: > > >>>>>>> KYLIN-978 will clean all hdfs path except cuboid files after > > >>> buildJob > > >>>>>>> and mergeJob completed. > > >>>>>>> The hdfs path will not be cleanup if a job was discarded, we > need > > >>>>>>> improvement on this. > > >>>>>>> > > >>>>>>> > > >>>>>>> Best Regards, > > >>>>>>> Yerui Sun > > >>>>>>> [email protected] > > >>>>>>> > > >>>>>>> > > >>>>>>> > > >>>>>>>> 在 2015年9月10日，18:20，yu feng <[email protected]> 写道： > > >>>>>>>> > > >>>>>>>> I see this core Improvement in release 1.0, JIRA url : > > >>>>>>>> https://issues.apache.org/jira/browse/KYLIN-926 > > >>>>>>>> > > >>>>>>>> However, after my test and check the source code , I find some > > >>>>>>> rubbish(I am not > > >>>>>>>> sure) file in HDFS. > > >>>>>>>> > > >>>>>>>> First, kylin only drop the Intermediate table in hive, but the > > >>> table > > >>>>>>> is > > >>>>>>> an > > >>>>>>>> EXTERNAL table, the file still exist in kylin tmp directory in > > >>> HDFS(I > > >>>>>>> check > > >>>>>>>> that..) > > >>>>>>>> > > >>>>>>>> Second, the cuboid files take a large space in HDFS, and kylin > do > > >>> not > > >>>>>>>> delete after the cube build(fact_distinct_columns files exist > > >> too). > > >>>>>>> I am > > >>>>>>>> not sure if those has other effects, remind me please if it > has.. > > >>>>>>>> > > >>>>>>>> Third, After I discard a job, I think kylin should delete the > > >>>>>>> Intermediate > > >>>>>>>> files and drop Intermediate hive table, even though delete > > >>>>>>>> them asynchronous. I think those data do not have any > > >>>>>>> effects..remind me > > >>>>>>>> please if it has.. > > >>>>>>>> > > >>>>>>>> These are rubbish datas still exist in current > > >> version(kylin-1.0), > > >>>>>>> please > > >>>>>>>> check, thanks.. > > >>>>>>> > > >>>>>>> > > >>>>>> > > >>>> > > >>>> > > >>> > > >> > > > > >
