Re: OutOfDirectMemoryError for Spark 2.2

2018-03-12 Thread Dave Cameron 
I believe jmap is only showing you the java heap used, but the program is
running out of direct memory space. They are two different pools of memory.

I haven't had to diagnose a direct memory problem before, but this blog
post has some suggestions of how to do it:
https://jkutner.github.io/2017/04/28/oh-the-places-your-java-memory-goes.html


On Thu, Mar 8, 2018 at 1:57 AM, Chawla,Sumit  wrote:

> Hi
>
> Anybody got any pointers on this one?
>
> Regards
> Sumit Chawla
>
>
> On Tue, Mar 6, 2018 at 8:58 AM, Chawla,Sumit 
> wrote:
>
>> No,  This is the only Stack trace i get.  I have tried DEBUG but didn't
>> notice much of a log change.
>>
>> Yes,  I have tried bumping MaxDirectMemorySize to get rid of this error.
>> It does work if i throw 4G+ memory at it.  However,  I am trying to
>> understand this behavior so that i can setup this number to appropriate
>> value.
>>
>> Regards
>> Sumit Chawla
>>
>>
>> On Tue, Mar 6, 2018 at 8:07 AM, Vadim Semenov 
>> wrote:
>>
>>> Do you have a trace? i.e. what's the source of `io.netty.*` calls?
>>>
>>> And have you tried bumping `-XX:MaxDirectMemorySize`?
>>>
>>> On Tue, Mar 6, 2018 at 12:45 AM, Chawla,Sumit 
>>> wrote:
>>>
 Hi All

 I have a job which processes a large dataset.  All items in the dataset
 are unrelated.  To save on cluster resources,  I process these items in
 chunks.  Since chunks are independent of each other,  I start and shut down
 the spark context for each chunk.  This allows me to keep DAG smaller and
 not retry the entire DAG in case of failures.   This mechanism used to work
 fine with Spark 1.6.  Now,  as we have moved to 2.2,  the job started
 failing with OutOfDirectMemoryError error.

 2018-03-03 22:00:59,687 WARN  [rpc-server-48-1]
 server.TransportChannelHandler 
 (TransportChannelHandler.java:exceptionCaught(78))
 - Exception in connection from /10.66.73.27:60374

 io.netty.util.internal.OutOfDirectMemoryError: failed to allocate
 8388608 byte(s) of direct memory (used: 1023410176, max: 1029177344)

 at io.netty.util.internal.PlatformDependent.incrementMemoryCoun
 ter(PlatformDependent.java:506)

 at io.netty.util.internal.PlatformDependent.allocateDirectNoCle
 aner(PlatformDependent.java:460)

 at io.netty.buffer.PoolArena$DirectArena.allocateDirect(PoolAre
 na.java:701)

 at io.netty.buffer.PoolArena$DirectArena.newChunk(PoolArena.java:690)

 at io.netty.buffer.PoolArena.allocateNormal(PoolArena.java:237)

 at io.netty.buffer.PoolArena.allocate(PoolArena.java:213)

 at io.netty.buffer.PoolArena.allocate(PoolArena.java:141)

 at io.netty.buffer.PooledByteBufAllocator.newDirectBuffer(Poole
 dByteBufAllocator.java:271)

 at io.netty.buffer.AbstractByteBufAllocator.directBuffer(Abstra
 ctByteBufAllocator.java:177)

 at io.netty.buffer.AbstractByteBufAllocator.directBuffer(Abstra
 ctByteBufAllocator.java:168)

 at io.netty.buffer.AbstractByteBufAllocator.ioBuffer(AbstractBy
 teBufAllocator.java:129)

 at io.netty.channel.AdaptiveRecvByteBufAllocator$HandleImpl.all
 ocate(AdaptiveRecvByteBufAllocator.java:104)

 at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.re
 ad(AbstractNioByteChannel.java:117)

 at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEven
 tLoop.java:564)

 I got some clue on what is causing this from https://github.com/netty/
 netty/issues/6343,  However I am not able to add up numbers on what is
 causing 1 GB of Direct Memory to fill up.

 Output from jmap


 7: 22230 1422720 io.netty.buffer.PoolSubpage

 12: 1370 804640 io.netty.buffer.PoolSubpage[]

 41: 3600 144000 io.netty.buffer.PoolChunkList

 98: 1440 46080 io.netty.buffer.PoolThreadCache$SubPageMemoryRegionCache

 113: 300 40800 io.netty.buffer.PoolArena$HeapArena

 114: 300 40800 io.netty.buffer.PoolArena$DirectArena

 192: 198 15840 io.netty.buffer.PoolChunk

 274: 120 8320 io.netty.buffer.PoolThreadCache$MemoryRegionCache[]

 406: 120 3840 io.netty.buffer.PoolThreadCache$NormalMemoryRegionCache

 422: 72 3552 io.netty.buffer.PoolArena[]

 458: 30 2640 io.netty.buffer.PooledUnsafeDirectByteBuf

 500: 36 2016 io.netty.buffer.PooledByteBufAllocator

 529: 32 1792 io.netty.buffer.UnpooledUnsafeHeapByteBuf

 589: 20 1440 io.netty.buffer.PoolThreadCache

 630: 37 1184 io.netty.buffer.EmptyByteBuf

 703: 36 864 io.netty.buffer.PooledByteBufAllocator$PoolThreadLocalCache

 852: 22 528 io.netty.buffer.AdvancedLeakAwareByteBuf

 889: 10 480 io.netty.buffer.SlicedAbstractByteBuf

 917: 8 448 io.netty.buffer.UnpooledHeapByteBuf

 1018: 20 320

Re: OutOfDirectMemoryError for Spark 2.2

2018-03-07 Thread Chawla,Sumit 
Hi

Anybody got any pointers on this one?

Regards
Sumit Chawla


On Tue, Mar 6, 2018 at 8:58 AM, Chawla,Sumit  wrote:

> No,  This is the only Stack trace i get.  I have tried DEBUG but didn't
> notice much of a log change.
>
> Yes,  I have tried bumping MaxDirectMemorySize to get rid of this error.
> It does work if i throw 4G+ memory at it.  However,  I am trying to
> understand this behavior so that i can setup this number to appropriate
> value.
>
> Regards
> Sumit Chawla
>
>
> On Tue, Mar 6, 2018 at 8:07 AM, Vadim Semenov  wrote:
>
>> Do you have a trace? i.e. what's the source of `io.netty.*` calls?
>>
>> And have you tried bumping `-XX:MaxDirectMemorySize`?
>>
>> On Tue, Mar 6, 2018 at 12:45 AM, Chawla,Sumit 
>> wrote:
>>
>>> Hi All
>>>
>>> I have a job which processes a large dataset.  All items in the dataset
>>> are unrelated.  To save on cluster resources,  I process these items in
>>> chunks.  Since chunks are independent of each other,  I start and shut down
>>> the spark context for each chunk.  This allows me to keep DAG smaller and
>>> not retry the entire DAG in case of failures.   This mechanism used to work
>>> fine with Spark 1.6.  Now,  as we have moved to 2.2,  the job started
>>> failing with OutOfDirectMemoryError error.
>>>
>>> 2018-03-03 22:00:59,687 WARN  [rpc-server-48-1]
>>> server.TransportChannelHandler 
>>> (TransportChannelHandler.java:exceptionCaught(78))
>>> - Exception in connection from /10.66.73.27:60374
>>>
>>> io.netty.util.internal.OutOfDirectMemoryError: failed to allocate
>>> 8388608 byte(s) of direct memory (used: 1023410176, max: 1029177344)
>>>
>>> at io.netty.util.internal.PlatformDependent.incrementMemoryCoun
>>> ter(PlatformDependent.java:506)
>>>
>>> at io.netty.util.internal.PlatformDependent.allocateDirectNoCle
>>> aner(PlatformDependent.java:460)
>>>
>>> at io.netty.buffer.PoolArena$DirectArena.allocateDirect(PoolAre
>>> na.java:701)
>>>
>>> at io.netty.buffer.PoolArena$DirectArena.newChunk(PoolArena.java:690)
>>>
>>> at io.netty.buffer.PoolArena.allocateNormal(PoolArena.java:237)
>>>
>>> at io.netty.buffer.PoolArena.allocate(PoolArena.java:213)
>>>
>>> at io.netty.buffer.PoolArena.allocate(PoolArena.java:141)
>>>
>>> at io.netty.buffer.PooledByteBufAllocator.newDirectBuffer(Poole
>>> dByteBufAllocator.java:271)
>>>
>>> at io.netty.buffer.AbstractByteBufAllocator.directBuffer(Abstra
>>> ctByteBufAllocator.java:177)
>>>
>>> at io.netty.buffer.AbstractByteBufAllocator.directBuffer(Abstra
>>> ctByteBufAllocator.java:168)
>>>
>>> at io.netty.buffer.AbstractByteBufAllocator.ioBuffer(AbstractBy
>>> teBufAllocator.java:129)
>>>
>>> at io.netty.channel.AdaptiveRecvByteBufAllocator$HandleImpl.all
>>> ocate(AdaptiveRecvByteBufAllocator.java:104)
>>>
>>> at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.re
>>> ad(AbstractNioByteChannel.java:117)
>>>
>>> at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEven
>>> tLoop.java:564)
>>>
>>> I got some clue on what is causing this from https://github.com/netty/
>>> netty/issues/6343,  However I am not able to add up numbers on what is
>>> causing 1 GB of Direct Memory to fill up.
>>>
>>> Output from jmap
>>>
>>>
>>> 7: 22230 1422720 io.netty.buffer.PoolSubpage
>>>
>>> 12: 1370 804640 io.netty.buffer.PoolSubpage[]
>>>
>>> 41: 3600 144000 io.netty.buffer.PoolChunkList
>>>
>>> 98: 1440 46080 io.netty.buffer.PoolThreadCache$SubPageMemoryRegionCache
>>>
>>> 113: 300 40800 io.netty.buffer.PoolArena$HeapArena
>>>
>>> 114: 300 40800 io.netty.buffer.PoolArena$DirectArena
>>>
>>> 192: 198 15840 io.netty.buffer.PoolChunk
>>>
>>> 274: 120 8320 io.netty.buffer.PoolThreadCache$MemoryRegionCache[]
>>>
>>> 406: 120 3840 io.netty.buffer.PoolThreadCache$NormalMemoryRegionCache
>>>
>>> 422: 72 3552 io.netty.buffer.PoolArena[]
>>>
>>> 458: 30 2640 io.netty.buffer.PooledUnsafeDirectByteBuf
>>>
>>> 500: 36 2016 io.netty.buffer.PooledByteBufAllocator
>>>
>>> 529: 32 1792 io.netty.buffer.UnpooledUnsafeHeapByteBuf
>>>
>>> 589: 20 1440 io.netty.buffer.PoolThreadCache
>>>
>>> 630: 37 1184 io.netty.buffer.EmptyByteBuf
>>>
>>> 703: 36 864 io.netty.buffer.PooledByteBufAllocator$PoolThreadLocalCache
>>>
>>> 852: 22 528 io.netty.buffer.AdvancedLeakAwareByteBuf
>>>
>>> 889: 10 480 io.netty.buffer.SlicedAbstractByteBuf
>>>
>>> 917: 8 448 io.netty.buffer.UnpooledHeapByteBuf
>>>
>>> 1018: 20 320 io.netty.buffer.PoolThreadCache$1
>>>
>>> 1305: 4 128 io.netty.buffer.PoolThreadCache$MemoryRegionCache$Entry
>>>
>>> 1404: 1 80 io.netty.buffer.PooledUnsafeHeapByteBuf
>>>
>>> 1473: 3 72 io.netty.buffer.PoolArena$SizeClass
>>>
>>> 1529: 1 64 io.netty.buffer.AdvancedLeakAwareCompositeByteBuf
>>>
>>> 1541: 2 64 io.netty.buffer.CompositeByteBuf$Component
>>>
>>> 1568: 1 56 io.netty.buffer.CompositeByteBuf
>>>
>>> 1896: 1 32 io.netty.buffer.PoolArena$SizeClass[]
>>>
>>> 2042: 1 24 io.netty.buffer.PooledUnsafeDirectByteBuf$1
>>>
>>> 2046: 1 24

Re: OutOfDirectMemoryError for Spark 2.2

2018-03-06 Thread Chawla,Sumit 
No,  This is the only Stack trace i get.  I have tried DEBUG but didn't
notice much of a log change.

Yes,  I have tried bumping MaxDirectMemorySize to get rid of this error.
It does work if i throw 4G+ memory at it.  However,  I am trying to
understand this behavior so that i can setup this number to appropriate
value.

Regards
Sumit Chawla


On Tue, Mar 6, 2018 at 8:07 AM, Vadim Semenov  wrote:

> Do you have a trace? i.e. what's the source of `io.netty.*` calls?
>
> And have you tried bumping `-XX:MaxDirectMemorySize`?
>
> On Tue, Mar 6, 2018 at 12:45 AM, Chawla,Sumit 
> wrote:
>
>> Hi All
>>
>> I have a job which processes a large dataset.  All items in the dataset
>> are unrelated.  To save on cluster resources,  I process these items in
>> chunks.  Since chunks are independent of each other,  I start and shut down
>> the spark context for each chunk.  This allows me to keep DAG smaller and
>> not retry the entire DAG in case of failures.   This mechanism used to work
>> fine with Spark 1.6.  Now,  as we have moved to 2.2,  the job started
>> failing with OutOfDirectMemoryError error.
>>
>> 2018-03-03 22:00:59,687 WARN  [rpc-server-48-1]
>> server.TransportChannelHandler 
>> (TransportChannelHandler.java:exceptionCaught(78))
>> - Exception in connection from /10.66.73.27:60374
>>
>> io.netty.util.internal.OutOfDirectMemoryError: failed to allocate
>> 8388608 byte(s) of direct memory (used: 1023410176, max: 1029177344)
>>
>> at io.netty.util.internal.PlatformDependent.incrementMemoryCoun
>> ter(PlatformDependent.java:506)
>>
>> at io.netty.util.internal.PlatformDependent.allocateDirectNoCle
>> aner(PlatformDependent.java:460)
>>
>> at io.netty.buffer.PoolArena$DirectArena.allocateDirect(PoolAre
>> na.java:701)
>>
>> at io.netty.buffer.PoolArena$DirectArena.newChunk(PoolArena.java:690)
>>
>> at io.netty.buffer.PoolArena.allocateNormal(PoolArena.java:237)
>>
>> at io.netty.buffer.PoolArena.allocate(PoolArena.java:213)
>>
>> at io.netty.buffer.PoolArena.allocate(PoolArena.java:141)
>>
>> at io.netty.buffer.PooledByteBufAllocator.newDirectBuffer(Poole
>> dByteBufAllocator.java:271)
>>
>> at io.netty.buffer.AbstractByteBufAllocator.directBuffer(Abstra
>> ctByteBufAllocator.java:177)
>>
>> at io.netty.buffer.AbstractByteBufAllocator.directBuffer(Abstra
>> ctByteBufAllocator.java:168)
>>
>> at io.netty.buffer.AbstractByteBufAllocator.ioBuffer(AbstractBy
>> teBufAllocator.java:129)
>>
>> at io.netty.channel.AdaptiveRecvByteBufAllocator$HandleImpl.
>> allocate(AdaptiveRecvByteBufAllocator.java:104)
>>
>> at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.
>> read(AbstractNioByteChannel.java:117)
>>
>> at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEven
>> tLoop.java:564)
>>
>> I got some clue on what is causing this from https://github.com/netty/
>> netty/issues/6343,  However I am not able to add up numbers on what is
>> causing 1 GB of Direct Memory to fill up.
>>
>> Output from jmap
>>
>>
>> 7: 22230 1422720 io.netty.buffer.PoolSubpage
>>
>> 12: 1370 804640 io.netty.buffer.PoolSubpage[]
>>
>> 41: 3600 144000 io.netty.buffer.PoolChunkList
>>
>> 98: 1440 46080 io.netty.buffer.PoolThreadCache$SubPageMemoryRegionCache
>>
>> 113: 300 40800 io.netty.buffer.PoolArena$HeapArena
>>
>> 114: 300 40800 io.netty.buffer.PoolArena$DirectArena
>>
>> 192: 198 15840 io.netty.buffer.PoolChunk
>>
>> 274: 120 8320 io.netty.buffer.PoolThreadCache$MemoryRegionCache[]
>>
>> 406: 120 3840 io.netty.buffer.PoolThreadCache$NormalMemoryRegionCache
>>
>> 422: 72 3552 io.netty.buffer.PoolArena[]
>>
>> 458: 30 2640 io.netty.buffer.PooledUnsafeDirectByteBuf
>>
>> 500: 36 2016 io.netty.buffer.PooledByteBufAllocator
>>
>> 529: 32 1792 io.netty.buffer.UnpooledUnsafeHeapByteBuf
>>
>> 589: 20 1440 io.netty.buffer.PoolThreadCache
>>
>> 630: 37 1184 io.netty.buffer.EmptyByteBuf
>>
>> 703: 36 864 io.netty.buffer.PooledByteBufAllocator$PoolThreadLocalCache
>>
>> 852: 22 528 io.netty.buffer.AdvancedLeakAwareByteBuf
>>
>> 889: 10 480 io.netty.buffer.SlicedAbstractByteBuf
>>
>> 917: 8 448 io.netty.buffer.UnpooledHeapByteBuf
>>
>> 1018: 20 320 io.netty.buffer.PoolThreadCache$1
>>
>> 1305: 4 128 io.netty.buffer.PoolThreadCache$MemoryRegionCache$Entry
>>
>> 1404: 1 80 io.netty.buffer.PooledUnsafeHeapByteBuf
>>
>> 1473: 3 72 io.netty.buffer.PoolArena$SizeClass
>>
>> 1529: 1 64 io.netty.buffer.AdvancedLeakAwareCompositeByteBuf
>>
>> 1541: 2 64 io.netty.buffer.CompositeByteBuf$Component
>>
>> 1568: 1 56 io.netty.buffer.CompositeByteBuf
>>
>> 1896: 1 32 io.netty.buffer.PoolArena$SizeClass[]
>>
>> 2042: 1 24 io.netty.buffer.PooledUnsafeDirectByteBuf$1
>>
>> 2046: 1 24 io.netty.buffer.UnpooledByteBufAllocator
>>
>> 2051: 1 24 io.netty.buffer.PoolThreadCache$MemoryRegionCache$1
>>
>> 2078: 1 24 io.netty.buffer.PooledHeapByteBuf$1
>>
>> 2135: 1 24 io.netty.buffer.PooledUnsafeHeapByteBuf$1
>>
>> 2302: 1 16 io.netty.buffer.ByteBufUtil$1
>>
>> 2769: 1 16

Re: OutOfDirectMemoryError for Spark 2.2

2018-03-06 Thread Vadim Semenov 
Do you have a trace? i.e. what's the source of `io.netty.*` calls?

And have you tried bumping `-XX:MaxDirectMemorySize`?

On Tue, Mar 6, 2018 at 12:45 AM, Chawla,Sumit 
wrote:

> Hi All
>
> I have a job which processes a large dataset.  All items in the dataset
> are unrelated.  To save on cluster resources,  I process these items in
> chunks.  Since chunks are independent of each other,  I start and shut down
> the spark context for each chunk.  This allows me to keep DAG smaller and
> not retry the entire DAG in case of failures.   This mechanism used to work
> fine with Spark 1.6.  Now,  as we have moved to 2.2,  the job started
> failing with OutOfDirectMemoryError error.
>
> 2018-03-03 22:00:59,687 WARN  [rpc-server-48-1]
> server.TransportChannelHandler 
> (TransportChannelHandler.java:exceptionCaught(78))
> - Exception in connection from /10.66.73.27:60374
>
> io.netty.util.internal.OutOfDirectMemoryError: failed to allocate 8388608
> byte(s) of direct memory (used: 1023410176, max: 1029177344)
>
> at io.netty.util.internal.PlatformDependent.incrementMemoryCounter(
> PlatformDependent.java:506)
>
> at io.netty.util.internal.PlatformDependent.allocateDirectNoCleaner(
> PlatformDependent.java:460)
>
> at io.netty.buffer.PoolArena$DirectArena.allocateDirect(
> PoolArena.java:701)
>
> at io.netty.buffer.PoolArena$DirectArena.newChunk(PoolArena.java:690)
>
> at io.netty.buffer.PoolArena.allocateNormal(PoolArena.java:237)
>
> at io.netty.buffer.PoolArena.allocate(PoolArena.java:213)
>
> at io.netty.buffer.PoolArena.allocate(PoolArena.java:141)
>
> at io.netty.buffer.PooledByteBufAllocator.newDirectBuffer(
> PooledByteBufAllocator.java:271)
>
> at io.netty.buffer.AbstractByteBufAllocator.directBuffer(
> AbstractByteBufAllocator.java:177)
>
> at io.netty.buffer.AbstractByteBufAllocator.directBuffer(
> AbstractByteBufAllocator.java:168)
>
> at io.netty.buffer.AbstractByteBufAllocator.ioBuffer(
> AbstractByteBufAllocator.java:129)
>
> at io.netty.channel.AdaptiveRecvByteBufAllocator$HandleImpl.allocate(
> AdaptiveRecvByteBufAllocator.java:104)
>
> at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(
> AbstractNioByteChannel.java:117)
>
> at io.netty.channel.nio.NioEventLoop.processSelectedKey(
> NioEventLoop.java:564)
>
> I got some clue on what is causing this from https://github.com/netty/
> netty/issues/6343,  However I am not able to add up numbers on what is
> causing 1 GB of Direct Memory to fill up.
>
> Output from jmap
>
>
> 7: 22230 1422720 io.netty.buffer.PoolSubpage
>
> 12: 1370 804640 io.netty.buffer.PoolSubpage[]
>
> 41: 3600 144000 io.netty.buffer.PoolChunkList
>
> 98: 1440 46080 io.netty.buffer.PoolThreadCache$SubPageMemoryRegionCache
>
> 113: 300 40800 io.netty.buffer.PoolArena$HeapArena
>
> 114: 300 40800 io.netty.buffer.PoolArena$DirectArena
>
> 192: 198 15840 io.netty.buffer.PoolChunk
>
> 274: 120 8320 io.netty.buffer.PoolThreadCache$MemoryRegionCache[]
>
> 406: 120 3840 io.netty.buffer.PoolThreadCache$NormalMemoryRegionCache
>
> 422: 72 3552 io.netty.buffer.PoolArena[]
>
> 458: 30 2640 io.netty.buffer.PooledUnsafeDirectByteBuf
>
> 500: 36 2016 io.netty.buffer.PooledByteBufAllocator
>
> 529: 32 1792 io.netty.buffer.UnpooledUnsafeHeapByteBuf
>
> 589: 20 1440 io.netty.buffer.PoolThreadCache
>
> 630: 37 1184 io.netty.buffer.EmptyByteBuf
>
> 703: 36 864 io.netty.buffer.PooledByteBufAllocator$PoolThreadLocalCache
>
> 852: 22 528 io.netty.buffer.AdvancedLeakAwareByteBuf
>
> 889: 10 480 io.netty.buffer.SlicedAbstractByteBuf
>
> 917: 8 448 io.netty.buffer.UnpooledHeapByteBuf
>
> 1018: 20 320 io.netty.buffer.PoolThreadCache$1
>
> 1305: 4 128 io.netty.buffer.PoolThreadCache$MemoryRegionCache$Entry
>
> 1404: 1 80 io.netty.buffer.PooledUnsafeHeapByteBuf
>
> 1473: 3 72 io.netty.buffer.PoolArena$SizeClass
>
> 1529: 1 64 io.netty.buffer.AdvancedLeakAwareCompositeByteBuf
>
> 1541: 2 64 io.netty.buffer.CompositeByteBuf$Component
>
> 1568: 1 56 io.netty.buffer.CompositeByteBuf
>
> 1896: 1 32 io.netty.buffer.PoolArena$SizeClass[]
>
> 2042: 1 24 io.netty.buffer.PooledUnsafeDirectByteBuf$1
>
> 2046: 1 24 io.netty.buffer.UnpooledByteBufAllocator
>
> 2051: 1 24 io.netty.buffer.PoolThreadCache$MemoryRegionCache$1
>
> 2078: 1 24 io.netty.buffer.PooledHeapByteBuf$1
>
> 2135: 1 24 io.netty.buffer.PooledUnsafeHeapByteBuf$1
>
> 2302: 1 16 io.netty.buffer.ByteBufUtil$1
>
> 2769: 1 16 io.netty.util.internal.__matchers__.io.netty.buffer.
> ByteBufMatcher
>
>
>
> My Driver machine has 32 CPUs,  and as of now i have 15 machines in my
> cluster.   As of now, the error happens on processing 5th or 6th chunk.  I
> suspect the error is dependent on number of Executors and would happen
> early if we add more executors.
>
>
> I am trying to come up an explanation of what is filling up the Direct
> Memory and how to quanitfy it as factor of Number of Executors.  Our
> cluster is shared cluster,  And we need to understand how much Driver
> Memory to allocate for most of the jobs.
>
>
>
>
>
>