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Accumulo >> mail # user >> OutOfMemoryError: Java heap space after data load

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Re: OutOfMemoryError: Java heap space after data load
There's no need to flush... the shell is flushing after every single line.

The flush you are invoking causes a minor compaction.

If you wrote a quick java program to ingest the data, the data would load
about 35x faster.

On Mon, Apr 29, 2013 at 6:40 PM, Terry P. <[EMAIL PROTECTED]> wrote:

> Perhaps having a configuration item to limit the size of the
> shell_history.txt file would help avoid this in future?
> On Mon, Apr 29, 2013 at 5:37 PM, Terry P. <[EMAIL PROTECTED]> wrote:
>> You hit it John -- on the NameNode the shell_history.txt file is 128MB,
>> and same thing on the DataNode that 99% of the data went to due to the key
>> structure.  On the other two datanodes it was tiny, and both could login
>> fine (just my luck that the only datanode I tried after the load was the
>> fat one).
>> So is --disable-tab-completion supposed to skip reading the
>> shell_history.txt file?  It appears that is not the case with 1.4.2 as it
>> still dies with OOM error.
>> I now see that a better way to go would probably be to use --execute-file
>> switch to read the load file rather than pipe it to the shell.  Correct?
>> On Mon, Apr 29, 2013 at 5:04 PM, John Vines <[EMAIL PROTECTED]> wrote:
>>> Depending on your answer to Eric's question, I wonder if your history is
>>> enough to blow it up. You may also want to check the size of
>>> ~/.accumulo/shell_history.txt and see if that is ginormous.
>>> On Mon, Apr 29, 2013 at 5:07 PM, Terry P. <[EMAIL PROTECTED]> wrote:
>>>> Hi John,
>>>> I attempted to start the shell with --disable-tab-completion but it
>>>> still failed in an identical manner.  What is that feature/option?
>>>> The ACCUMULO_OTHER_OPTS var was set to "-Xmx256m -Xms64m" via the 2GB
>>>> example config script.  I upped the -Xmx256m to 512m and the shell started
>>>> successfully, so thanks!
>>>> What would cause the shell to need more than 256m of memory just to
>>>> start?  I'd like to understand how to determine an appropriate value to set
>>>> Thanks,
>>>> Terry
>>>> On Mon, Apr 29, 2013 at 2:21 PM, John Vines <[EMAIL PROTECTED]> wrote:
>>>>> The shell gets it's memory config from the accumulo-env file from
>>>>> ACCUMULO_OTHER_OPTS. If, for some reason, the value was low or there was a
>>>>> lot of data being loaded for the tab completion stuff in the shell, it
>>>>> could die. You can try upping that value in the file or try running the
>>>>> shell with "--disable-tab-completion" to see if that helps.
>>>>> On Mon, Apr 29, 2013 at 3:02 PM, Terry P. <[EMAIL PROTECTED]> wrote:
>>>>>> Greetings folks,
>>>>>> I have stood up our 8-node Accumulo 1.4.2 cluster consisting of 3
>>>>>> ZooKeepers, 1 NameNode (also runs Accumulo Master, Monitor, and GC), and 3
>>>>>> DataNodes / TabletServers (Secondary NameNode with Alternate Accumulo
>>>>>> Master process will follow).  The initial config files were copied from the
>>>>>> 2GB/native-standalone directory.
>>>>>> For a quick test I have a text file I generated to load 500,000 rows
>>>>>> of sample data using the Accumulo shell.  For lack of a better place to run
>>>>>> it this first time, I ran it on the NameNode.  The script performs flushes
>>>>>> every 10,000 records (about 30,000 entries).  After the load finished, when
>>>>>> I attempt to login to the Accumulo Shell on the NameNode, I get the error:
>>>>>> [root@edib-namenode ~]# /usr/lib/accumulo/bin/accumulo shell -u
>>>>>> $AUSER -p $AUSERPWD
>>>>>> #
>>>>>> # java.lang.OutOfMemoryError: Java heap space
>>>>>> # -XX:OnOutOfMemoryError="kill -9 %p"
>>>>>> #   Executing /bin/sh -c "kill -9 24899"...
>>>>>> Killed
>>>>>> The performance of that test was pretty poor at about 160/second
>>>>>> (somewhat expected, as it was just one thread) so to keep moving I
>>>>>> generated 3 different load files and ran one on each of the 3 DataNodes /
>>>>>> TabletServers.  Performance was much better, sustaining 1,400 per second.