Thanks Jeff,
Much like RDBMS that caches data, the same I believe happens in Spark as well with 0n-memory operations. I ran each job three times to reduce the impact from physical IOs. It is mentioned below (three runs). I agree with you that this is only a test with two clusters but essentially all runs used the same hardware. Granted increasing the number of clusters will add to parallelism and will improve the performance of Hive on Spark. There is another pertinent argument here as this query returned only one line. If the data set was large I would have expected as I have seen before that Hive takes over as there will not be enough memory for Spark operations. Additionaly spark-sql does not support certain operations like creating temporary tables like below spark-sql> CREATE TEMPORARY TABLE tmp AS > SELECT t.calendar_month_desc, c.channel_desc, SUM(s.amount_sold) AS TotalSales > FROM sales s, times t, channels c > WHERE s.time_id = t.time_id > AND s.channel_id = c.channel_id > GROUP BY t.calendar_month_desc, c.channel_desc > ; Error in query: Unhandled clauses: TEMPORARY 1, 2,2, 7 Regards, Dr Mich Talebzadeh LinkedIn https://www.linkedin.com/profile/view?id=AAEAAAAWh2gBxianrbJd6zP6AcPCCdOABUrV8Pw Sybase ASE 15 Gold Medal Award 2008 A Winning Strategy: Running the most Critical Financial Data on ASE 15 http://login.sybase.com/files/Product_Overviews/ASE-Winning-Strategy-091908.pdf Author of the books "A Practitioner’s Guide to Upgrading to Sybase ASE 15", ISBN 978-0-9563693-0-7. co-author "Sybase Transact SQL Guidelines Best Practices", ISBN 978-0-9759693-0-4 Publications due shortly: Complex Event Processing in Heterogeneous Environments, ISBN: 978-0-9563693-3-8 Oracle and Sybase, Concepts and Contrasts, ISBN: 978-0-9563693-1-4, volume one out shortly http://talebzadehmich.wordpress.com <http://talebzadehmich.wordpress.com/> NOTE: The information in this email is proprietary and confidential. This message is for the designated recipient only, if you are not the intended recipient, you should destroy it immediately. Any information in this message shall not be understood as given or endorsed by Peridale Technology Ltd, its subsidiaries or their employees, unless expressly so stated. It is the responsibility of the recipient to ensure that this email is virus free, therefore neither Peridale Technology Ltd, its subsidiaries nor their employees accept any responsibility. From: Xuefu Zhang [mailto:xzh...@cloudera.com] Sent: 01 February 2016 03:05 To: user@hive.apache.org Subject: Re: Running Spark-sql on Hive metastore For Hive on Spark, there is a startup cost. The second run should be faster. More importantly, it looks like you have 18 map tasks but only your cluster only runs two of them at a time. Thus, you cluster is basically having only two way parallelism. If you configure your cluster to give more capacity to Hive, the speed should improve as well. Note that each your map task takes only seconds to complete. On Sun, Jan 31, 2016 at 3:07 PM, Mich Talebzadeh <m...@peridale.co.uk <mailto:m...@peridale.co.uk> > wrote: Hi, * Spark 1.5.2 on Hive 1.2.1 * Hive 1.2.1 on Spark 1.3.1 * Oracle Release 11.2.0.1.0 * Hadoop 2.6 I am running spark-sql using Hive metastore and I am pleasantly surprised by the speed by which Spark performs certain queries on Hive tables. I imported a 100 Million rows table from Oracle into a Hive staging table via Sqoop and then did an insert/select into an ORC table in Hive as defined below. +------------------------------------------------------------+--+ | createtab_stmt | +------------------------------------------------------------+--+ | CREATE TABLE `dummy`( | | `id` int, | | `clustered` int, | | `scattered` int, | | `randomised` int, | | `random_string` varchar(50), | | `small_vc` varchar(10), | | `padding` varchar(10)) | | CLUSTERED BY ( | | id) | | INTO 256 BUCKETS | | ROW FORMAT SERDE | | 'org.apache.hadoop.hive.ql.io.orc.OrcSerde' | | STORED AS INPUTFORMAT | | 'org.apache.hadoop.hive.ql.io.orc.OrcInputFormat' | | OUTPUTFORMAT | | 'org.apache.hadoop.hive.ql.io.orc.OrcOutputFormat' | | LOCATION | | 'hdfs://rhes564:9000/user/hive/warehouse/test.db/dummy' | | TBLPROPERTIES ( | | 'COLUMN_STATS_ACCURATE'='true', | | 'numFiles'='35', | | 'numRows'='100000000', | | 'orc.bloom.filter.columns'='ID', | | 'orc.bloom.filter.fpp'='0.05', | | 'orc.compress'='SNAPPY', | | 'orc.create.index'='true', | | 'orc.row.index.stride'='10000', | | 'orc.stripe.size'='16777216', | | 'rawDataSize'='33800000000', | | 'totalSize'='5660813776', | | 'transient_lastDdlTime'='1454234981') | +------------------------------------------------------------+--+ I am doing simple min,max functions on columns scattered and randomised from the above table that are not part of cluster etc in Hive. In addition, in Oracle there is no index on these columns as well. If I use Hive 1.2.1 on Spark 1.3.1 it comes back in 50.751 seconds select min(scattered), max(randomised) from dummy; INFO : Query Hive on Spark job[0] stages: INFO : 0 INFO : 1 INFO : Status: Running (Hive on Spark job[0]) INFO : Job Progress Format CurrentTime StageId_StageAttemptId: SucceededTasksCount(+RunningTasksCount-FailedTasksCount)/TotalTasksCount [StageCost] INFO : 2016-01-31 22:55:05,114 Stage-0_0: 0/18 Stage-1_0: 0/1 INFO : 2016-01-31 22:55:06,122 Stage-0_0: 0(+2)/18 Stage-1_0: 0/1 INFO : 2016-01-31 22:55:09,165 Stage-0_0: 0(+2)/18 Stage-1_0: 0/1 INFO : 2016-01-31 22:55:12,190 Stage-0_0: 2(+2)/18 Stage-1_0: 0/1 INFO : 2016-01-31 22:55:14,201 Stage-0_0: 3(+2)/18 Stage-1_0: 0/1 INFO : 2016-01-31 22:55:15,209 Stage-0_0: 4(+2)/18 Stage-1_0: 0/1 INFO : 2016-01-31 22:55:17,218 Stage-0_0: 6(+2)/18 Stage-1_0: 0/1 INFO : 2016-01-31 22:55:20,234 Stage-0_0: 8(+2)/18 Stage-1_0: 0/1 INFO : 2016-01-31 22:55:22,245 Stage-0_0: 10(+2)/18 Stage-1_0: 0/1 INFO : 2016-01-31 22:55:25,257 Stage-0_0: 12(+2)/18 Stage-1_0: 0/1 INFO : 2016-01-31 22:55:27,270 Stage-0_0: 14(+2)/18 Stage-1_0: 0/1 INFO : 2016-01-31 22:55:30,289 Stage-0_0: 16(+2)/18 Stage-1_0: 0/1 INFO : 2016-01-31 22:55:31,294 Stage-0_0: 17(+1)/18 Stage-1_0: 0/1 INFO : 2016-01-31 22:55:32,302 Stage-0_0: 18/18 Finished Stage-1_0: 0(+1)/1 INFO : 2016-01-31 22:55:33,309 Stage-0_0: 18/18 Finished Stage-1_0: 1/1 Finished INFO : Status: Finished successfully in 46.37 seconds +------+------+--+ | _c0 | _c1 | +------+------+--+ | 0 | 999 | +------+------+--+ 1 row selected (50.751 seconds) If I use Spark 1.5.2 on Hive 1.2.1 it comes back in 7.37 seconds (three runs) select min(scattered), max(randomised) from dummy; 16/01/31 22:59:30 INFO parse.ParseDriver: Parsing command: select min(scattered), max(randomised) from dummy 16/01/31 22:59:30 INFO parse.ParseDriver: Parse Completed 16/01/31 22:59:30 INFO Configuration.deprecation: mapred.map.tasks is deprecated. Instead, use mapreduce.job.maps 16/01/31 22:59:30 INFO storage.MemoryStore: ensureFreeSpace(480952) called with curMem=4732, maxMem=555684986 16/01/31 22:59:30 INFO storage.MemoryStore: Block broadcast_1 stored as values in memory (estimated size 469.7 KB, free 529.5 MB) 16/01/31 22:59:31 INFO storage.MemoryStore: ensureFreeSpace(41724) called with curMem=485684, maxMem=555684986 16/01/31 22:59:31 INFO storage.MemoryStore: Block broadcast_1_piece0 stored as bytes in memory (estimated size 40.7 KB, free 529.4 MB) 16/01/31 22:59:31 INFO storage.BlockManagerInfo: Added broadcast_1_piece0 in memory on 50.140.197.217:50516 <http://50.140.197.217:50516> (size: 40.7 KB, free: 529.9 MB) 16/01/31 22:59:31 INFO spark.SparkContext: Created broadcast 1 from processCmd at CliDriver.java:376 16/01/31 22:59:31 INFO spark.SparkContext: Starting job: processCmd at CliDriver.java:376 16/01/31 22:59:31 INFO log.PerfLogger: <PERFLOG method=OrcGetSplits from=org.apache.hadoop.hive.ql.io.orc.ReaderImpl> 16/01/31 22:59:31 INFO Configuration.deprecation: mapred.input.dir is deprecated. Instead, use mapreduce.input.fileinputformat.inputdir 16/01/31 22:59:31 INFO orc.OrcInputFormat: FooterCacheHitRatio: 0/0 16/01/31 22:59:31 INFO log.PerfLogger: </PERFLOG method=OrcGetSplits start=1454281171262 end=1454281171330 duration=68 from=org.apache.hadoop.hive.ql.io.orc.ReaderImpl> 16/01/31 22:59:31 INFO scheduler.DAGScheduler: Registering RDD 6 (processCmd at CliDriver.java:376) 16/01/31 22:59:38 INFO scheduler.StatsReportListener: 0% 5% 10% 25% 50% 75% 90% 95% 100% 16/01/31 22:59:38 INFO scheduler.StatsReportListener: 0.0 ms 0.0 ms 0.0 ms 0.0 ms 0.0 ms 0.0 ms 0.0 ms 0.0 ms 0.0 ms 0 999 Time taken: 7.37 seconds, Fetched 1 row(s) Actually sounds like for a full table scan on 100 Million rows table Spark is on par with Oracle 11g that returns the same results in 7.03 seconds (three runs) doing a full table scan as expected scratch...@mydb.mich.LOCAL <mailto:scratch...@mydb.mich.LOCAL> > select min(scattered), max(randomised) from dummy; MIN(SCATTERED) MAX(RANDOMISED) -------------- --------------- 0 999 Elapsed: 00:00:07.03 Execution Plan ---------------------------------------------------------- Plan hash value: 2937163428 ---------------------------------------------------------------------------- | Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | ---------------------------------------------------------------------------- | 0 | SELECT STATEMENT | | 1 | 8 | 260K (1)| 00:52:12 | | 1 | SORT AGGREGATE | | 1 | 8 | | | | 2 | TABLE ACCESS FULL| DUMMY | 100M| 762M| 260K (1)| 00:52:12 | ---------------------------------------------------------------------------- Statistics ---------------------------------------------------------- 0 recursive calls 0 db block gets 1347179 consistent gets 1347168 physical reads 0 redo size 612 bytes sent via SQL*Net to client 523 bytes received via SQL*Net from client 2 SQL*Net roundtrips to/from client 0 sorts (memory) 0 sorts (disk) 1 rows processed Dr Mich Talebzadeh LinkedIn https://www.linkedin.com/profile/view?id=AAEAAAAWh2gBxianrbJd6zP6AcPCCdOABUrV8Pw Sybase ASE 15 Gold Medal Award 2008 A Winning Strategy: Running the most Critical Financial Data on ASE 15 http://login.sybase.com/files/Product_Overviews/ASE-Winning-Strategy-091908.pdf Author of the books "A Practitioner’s Guide to Upgrading to Sybase ASE 15", ISBN 978-0-9563693-0-7. co-author "Sybase Transact SQL Guidelines Best Practices", ISBN 978-0-9759693-0-4 Publications due shortly: Complex Event Processing in Heterogeneous Environments, ISBN: 978-0-9563693-3-8 Oracle and Sybase, Concepts and Contrasts, ISBN: 978-0-9563693-1-4, volume one out shortly http://talebzadehmich.wordpress.com <http://talebzadehmich.wordpress.com/> NOTE: The information in this email is proprietary and confidential. This message is for the designated recipient only, if you are not the intended recipient, you should destroy it immediately. Any information in this message shall not be understood as given or endorsed by Peridale Technology Ltd, its subsidiaries or their employees, unless expressly so stated. It is the responsibility of the recipient to ensure that this email is virus free, therefore neither Peridale Technology Ltd, its subsidiaries nor their employees accept any responsibility.