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From Geoffry Roberts <threadedb...@gmail.com>
Subject Re: Out of memory when putting many rows in an Acc table
Date Wed, 01 Oct 2014 15:12:11 GMT
Thanks for the response.

The only reason I was creating q new BatchWriter periodically was to
determine if BatchWriter was holding on to memory even after a flush.   I
had memory on my BatchWriterConfig set to 1M already.  I am reading my RDB
tables in pages of 10K rows.

Bumping up the JVM size didn't help,

I tried setting -XX:+HeapDumpOnOutOfMemoryError and when it did not produce
any output (hprof file). I realized this could be due to an inability by
the JVM to create additional native threads.

What I now think is the problem is not with Acc directly but hiding out on
the JDBC side.

Perhaps this is not an Acc issue at all but merely masquerading as one.
We'll see.

On Tue, Sep 30, 2014 at 12:17 PM, Josh Elser <josh.elser@gmail.com> wrote:

> You shouldn't have to create a new BatchWriter -- have you tried reducing
> the amount of memory the BatchWriter will use? It keeps a cache internally
> to try to do an amortization of Mutations to send to a given tabletserver.
>
> To limit this memory, use the BatchWriterConfig#setMaxMemory(long)
> method. By default, the maxMemory value is set to 50MB. Reducing this may
> be enough to hold less data in your client and give you some more head room.
>
> Alternatively, you could give your client JVM some more heap :)
>
>
> Geoffry Roberts wrote:
>
>> I am try to pump some data into Accumulo but I keep encountering
>>
>> Exception in thread "Thrift Connection Pool Checker"
>> java.lang.OutOfMemoryError: Java heap space
>>
>> at java.util.HashMap.newValueIterator(HashMap.java:971)
>>
>> at java.util.HashMap$Values.iterator(HashMap.java:1038)
>>
>> at
>> org.apache.accumulo.core.client.impl.ThriftTransportPool$Closer.
>> closeConnections(ThriftTransportPool.java:103)
>>
>> at
>> org.apache.accumulo.core.client.impl.ThriftTransportPool$Closer.
>> run(ThriftTransportPool.java:147)
>>
>> at java.lang.Thread.run(Thread.java:745)
>>
>>
>> I tried, as a work around, creating a new BatchWriter and closing the
>> old one every ten thousand rows, but to no avail.  Data gets written up
>> to the 200kth row, then the error.
>>
>> I have a table of 8M rows in a RDB that I am pumping into Acc via a
>> groovy script.  The rows are narrow, a short text field and four floats.
>>
>> I googled of course but nothing was helpful.  What can be done?
>>
>> Thanks so much.
>>
>> --
>> There are ways and there are ways,
>>
>> Geoffry Roberts
>>
>


-- 
There are ways and there are ways,

Geoffry Roberts

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