Do you mean running a multi-JVM 'cluster' on the single machine? How would
that affect performance/memory-consumption? If a multi-JVM setup can handle
such a large input, then why can't a single-JVM break down the job into
smaller tasks?

I also found that SPARK-9411 mentions making the page_size configurable but
it's hard-limited to ((1L << 31) - 1) * 8L [1]

[1]
https://github.com/apache/spark/blob/master/core/src/main/java/org/apache/spark/memory/TaskMemoryManager.java

​Spark-9452 also talks about larger page sizes but I don't know how that
affects my use case.​ [2]

[2] https://github.com/apache/spark/pull/7891


​The reason provided here is that the on-heap allocator's maximum page size
is limited by the maximum amount of data that can be stored in a long[]​.
Is it possible to force this specific operation to go off-heap so that it
can possibly use a bigger page size?



​>Babak​


*Babak Alipour ,*
*University of Florida*

On Fri, Sep 30, 2016 at 3:03 PM, Vadim Semenov <vadim.seme...@datadoghq.com>
wrote:

> Run more smaller executors: change `spark.executor.memory` to 32g and
> `spark.executor.cores` to 2-4, for example.
>
> Changing driver's memory won't help because it doesn't participate in
> execution.
>
> On Fri, Sep 30, 2016 at 2:58 PM, Babak Alipour <babak.alip...@gmail.com>
> wrote:
>
>> Thank you for your replies.
>>
>> @Mich, using LIMIT 100 in the query prevents the exception but given the
>> fact that there's enough memory, I don't think this should happen even
>> without LIMIT.
>>
>> @Vadim, here's the full stack trace:
>>
>> Caused by: java.lang.IllegalArgumentException: Cannot allocate a page
>> with more than 17179869176 bytes
>>         at org.apache.spark.memory.TaskMemoryManager.allocatePage(TaskM
>> emoryManager.java:241)
>>         at org.apache.spark.memory.MemoryConsumer.allocatePage(MemoryCo
>> nsumer.java:121)
>>         at org.apache.spark.util.collection.unsafe.sort.UnsafeExternalS
>> orter.acquireNewPageIfNecessary(UnsafeExternalSorter.java:374)
>>         at org.apache.spark.util.collection.unsafe.sort.UnsafeExternalS
>> orter.insertRecord(UnsafeExternalSorter.java:396)
>>         at org.apache.spark.sql.execution.UnsafeExternalRowSorter.inser
>> tRow(UnsafeExternalRowSorter.java:94)
>>         at org.apache.spark.sql.catalyst.expressions.GeneratedClass$Gen
>> eratedIterator.sort_addToSorter$(Unknown Source)
>>         at org.apache.spark.sql.catalyst.expressions.GeneratedClass$Gen
>> eratedIterator.agg_doAggregateWithoutKey$(Unknown Source)
>>         at org.apache.spark.sql.catalyst.expressions.GeneratedClass$Gen
>> eratedIterator.processNext(Unknown Source)
>>         at org.apache.spark.sql.execution.BufferedRowIterator.hasNext(B
>> ufferedRowIterator.java:43)
>>         at org.apache.spark.sql.execution.WholeStageCodegenExec$$anonfu
>> n$8$$anon$1.hasNext(WholeStageCodegenExec.scala:370)
>>         at scala.collection.Iterator$$anon$11.hasNext(Iterator.scala:408)
>>         at org.apache.spark.shuffle.sort.BypassMergeSortShuffleWriter.w
>> rite(BypassMergeSortShuffleWriter.java:125)
>>         at org.apache.spark.scheduler.ShuffleMapTask.runTask(ShuffleMap
>> Task.scala:79)
>>         at org.apache.spark.scheduler.ShuffleMapTask.runTask(ShuffleMap
>> Task.scala:47)
>>         at org.apache.spark.scheduler.Task.run(Task.scala:85)
>>         at org.apache.spark.executor.Executor$TaskRunner.run(Executor.s
>> cala:274)
>>         at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPool
>> Executor.java:1142)
>>         at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoo
>> lExecutor.java:617)
>>         at java.lang.Thread.run(Thread.java:745)
>>
>> I'm running spark in local mode so there is only one executor, the driver
>> and spark.driver.memory is set to 64g. Changing the driver's memory doesn't
>> help.
>>
>> *Babak Alipour ,*
>> *University of Florida*
>>
>> On Fri, Sep 30, 2016 at 2:05 PM, Vadim Semenov <
>> vadim.seme...@datadoghq.com> wrote:
>>
>>> Can you post the whole exception stack trace?
>>> What are your executor memory settings?
>>>
>>> Right now I assume that it happens in UnsafeExternalRowSorter ->
>>> UnsafeExternalSorter:insertRecord
>>>
>>> Running more executors with lower `spark.executor.memory` should help.
>>>
>>>
>>> On Fri, Sep 30, 2016 at 12:57 PM, Babak Alipour <babak.alip...@gmail.com
>>> > wrote:
>>>
>>>> Greetings everyone,
>>>>
>>>> I'm trying to read a single field of a Hive table stored as Parquet in
>>>> Spark (~140GB for the entire table, this single field should be just a few
>>>> GB) and look at the sorted output using the following:
>>>>
>>>> sql("SELECT " + field + " FROM MY_TABLE ORDER BY " + field + " DESC")
>>>>
>>>> ​But this simple line of code gives:
>>>>
>>>> Caused by: java.lang.IllegalArgumentException: Cannot allocate a page
>>>> with more than 17179869176 bytes
>>>>
>>>> Same error for:
>>>>
>>>> sql("SELECT " + field + " FROM MY_TABLE).sort(field)
>>>>
>>>> and:
>>>>
>>>> sql("SELECT " + field + " FROM MY_TABLE).orderBy(field)
>>>>
>>>>
>>>> I'm running this on a machine with more than 200GB of RAM, running in
>>>> local mode with spark.driver.memory set to 64g.
>>>>
>>>> I do not know why it cannot allocate a big enough page, and why is it
>>>> trying to allocate such a big page in the first place?
>>>>
>>>> I hope someone with more knowledge of Spark can shed some light on
>>>> this. Thank you!
>>>>
>>>>
>>>> *​Best regards,​*
>>>> *Babak Alipour ,*
>>>> *University of Florida*
>>>>
>>>
>>>
>>
>

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