It has read everything. As you notice the timing of count is still smaller
in Spark 2.4
Spark 2.4
scala> spark.time(spark.read.json("/data/20200528"))
Time taken: 19691 ms
res61: org.apache.spark.sql.DataFrame = [created: bigint, id: string ... 5
more fields]
scala> spark.time(res61.count())
Time taken: 7113 ms
res64: Long = 2605349
Spark 3.0
scala> spark.time(spark.read.json("/data/20200528"))
20/06/29 08:06:53 WARN package: Truncated the string representation of a
plan since it was too large. This behavior can be adjusted by setting
'spark.sql.debug.maxToStringFields'.
Time taken: 849652 ms
res0: org.apache.spark.sql.DataFrame = [created: bigint, id: string ... 5
more fields]
scala> spark.time(res0.count())
Time taken: 8201 ms
res2: Long = 2605349
On Mon, Jun 29, 2020 at 7:45 AM ArtemisDev <arte...@dtechspace.com> wrote:
> Could you share your code? Are you sure you Spark 2.4 cluster had indeed
> read anything? Looks like the Input size field is empty under 2.4.
>
> -- ND
> On 6/27/20 7:58 PM, Sanjeev Mishra wrote:
>
>
> I have large amount of json files that Spark can read in 36 seconds but
> Spark 3.0 takes almost 33 minutes to read the same. On closer analysis,
> looks like Spark 3.0 is choosing different DAG than Spark 2.0. Does anyone
> have any idea what is going on? Is there any configuration problem with
> Spark 3.0.
>
> Here are the details:
>
> *Spark 2.4*
>
> Summary Metrics for 2203 Completed Tasks
> <http://10.0.0.8:4040/stages/stage/?id=0&attempt=0#tasksTitle>
> Metric Min 25th percentile Median 75th percentile Max
> Duration 0.0 ms 0.0 ms 0.0 ms 1.0 ms 62.0 ms
> GC Time 0.0 ms 0.0 ms 0.0 ms 0.0 ms 11.0 ms
> Showing 1 to 2 of 2 entries
> Aggregated Metrics by Executor
> Show 20 40 60 100 All entries
> Search:
> Executor ID Logs Address Task Time Total Tasks Failed Tasks Killed Tasks
> Succeeded
> Tasks Blacklisted
> driver
> 10.0.0.8:49159 36 s 2203 0 0 2203 false
>
>
> *Spark 3.0*
>
> Summary Metrics for 8 Completed Tasks
> <http://10.0.0.8:4040/stages/stage/?id=1&attempt=0&task.eventTimelinePageNumber=1&task.eventTimelinePageSize=47#tasksTitle>
> Metric Min 25th percentile Median 75th percentile Max
> Duration 3.8 min 4.0 min 4.1 min 4.4 min 5.0 min
> GC Time 3 s 3 s 3 s 4 s 4 s
> Input Size / Records 15.6 MiB / 51028 16.2 MiB / 53303 16.8 MiB / 55259 17.8
> MiB / 58148 20.2 MiB / 71624
> Showing 1 to 3 of 3 entries
> Aggregated Metrics by Executor
> Show 20 40 60 100 All entries
> Search:
> Executor ID Logs Address Task Time Total Tasks Failed Tasks Killed Tasks
> Succeeded
> Tasks Blacklisted Input Size / Records
> driver
> 10.0.0.8:50224 33 min 8 0 0 8 false 136.1 MiB / 451999
>
>
> The DAG is also different
> Spark 2.0 DAG
>
> [image: Screenshot 2020-06-27 16.30.26.png]
>
> Spark 3.0 DAG
>
> [image: Screenshot 2020-06-27 16.32.32.png]
>
>
>
