David,

First of all thank you for your help, the typo was the problem. Second the
reason I was using DataStream as my file type for my hdfs sink was because
when I had it as a SequenceFile, the sink was adding a lot of garbage data
to the file when it copied to the hdfs, which was causing undesired
behavior with my created hive table. When I changed to DataStream, it just
put the plain text in the file. With regard to the channels, that is
something I will definitely look at in order to fine tune the performance,
now that I have solved this problem I can look at that, I have fumbled
around with the memory channel playing with the capacity and
transitionCapacity attributes and I have run into choking of the channel,
just have to read more about it. I don't know if you have seen these before
but I've been looking at them
https://blog.cloudera.com/blog/2013/01/how-to-do-apache-flume-performance-tuning-part-1/
.

Thanks for your help,

Chris


On Thu, Oct 24, 2013 at 10:17 AM, DSuiter RDX <[email protected]> wrote:

> Christopher,
>
> I use a very similar setup. I had a similar problem for a while. The HDFS
> sink defaults are the tricky part - they are all pretty small, since they
> assume a high data velocity. The tricky part is that unless they are all
> explicitly declared as OFF, then they are on.
>
> So, your HDFS batch size parameter might be the problem. Also, I notice
> you need to capitalize the "S" in the hdfs.roll*S*ize parameter -
> camelcase got me on transactionCapacity once :-) not sure if this is
> copypasta from your config, but that will cause an issue with the param
> being respected, so in your case it would roll it at 1024 bytes, or about
> 10 lines of text probably.
>
> One question about your config, though - I notice you have the
> hdfs.fileType as DataStream for Avro, but you do not have a serializer of
> avro_event declared. In what format are your files being put into HDFS? As
> Avro-contained streams, or as aggregated text bodies with newline
> delimiters? I ask because this setup for us has led to us needing to unwrap
> Avro event files in MapReduce, which is tricky - if you are getting
> aggregate text, I have some reconfiguring to do.
>
> Other things to look out for are - make sure the HDFS file being written
> to doesn't close mid-stream, I have not seen that recover gracefully, I am
> getting OOME in my testbed right now due to something like that; and make
> sure your transaction capacity in your channels is high enough through the
> flow, my original one kept choking with a small transaction capacity from
> the first channel to the Avro sink.
>
>
> Good luck!
>
> *Devin Suiter*
> Jr. Data Solutions Software Engineer
> 100 Sandusky Street | 2nd Floor | Pittsburgh, PA 15212
> Google Voice: 412-256-8556 | www.rdx.com
>
>
> On Thu, Oct 24, 2013 at 9:44 AM, Christopher Surage <[email protected]>wrote:
>
>> Hello I am having an issue increasing the size of the file which get
>> written into my hdfs. I have tried playing with the rollCount attribute for
>> an hdfs sink but it seems to cap at 10 lines of text per file, with many
>> files written to the hdfs directory. Now one may see why I need to change
>> this.
>>
>> I have 2 boxes running
>> 1) uses a spooldir source to check for new log files copied to a specific
>> dir. It then sends the events to an avro sink through a mem channel to the
>> other box with the hdfs on it.
>>
>>
>>
>>
>> 2) uses an avro source and sends events to the hdfs sink.
>>
>>
>> configurations:
>>
>> 1.
>>  # Name the compnents of the agent
>> a1.sources = r1
>> a1.sinks = k1
>> a1.channels = c1
>>
>>
>> ###############Describe/configure the source#################
>> a1.sources.r1.type = spooldir
>> a1.sources.r1.spoolDir = /u1/csurage/flume_test
>> a1.sources.r1.channels = c1
>> #a1.sources.r1.fileHeader = true
>>
>>
>> ##############describe the sink#######################
>> # file roll sink
>> #a1.sinks.k1.type = file_roll
>> #a1.sinks.k1.sink.directory = /u1/csurage/target_flume
>>
>> # Avro sink
>> a1.sinks.k1.type = avro
>> a1.sinks.k1.hostname = 45.32.96.136
>> a1.sinks.k1.port = 9311
>>
>>
>> # Channel the sink connects to
>> a1.sinks.k1.channel = c1
>>
>> ################describe the channel##################
>> # use a channel which buffers events in memory
>> a1.channels.c1.type = memory
>> a1.channels.c1.byteCapacity = 0
>>
>>
>>
>> 2. note when I change any of the attributes in bold, the rollCount stays
>> at 10 line
>>     files written to the hdfs
>>
>> # Name the compnents of the agent
>> a1.sources = r1
>> a1.sinks = k1
>> a1.channels = c1
>>
>>
>> ###############Describe/configure the source#################
>> a1.sources.r1.type = avro
>> a1.sources.r1.bind = 45.32.96.136
>> a1.sources.r1.port = 9311
>> a1.sources.r1.channels = c1
>> #a1.sources.r1.fileHeader = true
>>
>>
>> ##############describe the sink#######################
>> # HDFS sink
>> a1.sinks.k1.type = hdfs
>> a1.sinks.k1.hdfs.path = /user/csurage/hive
>> a1.sinks.k1.hdfs.fileType = DataStream
>> *a1.sinks.k1.hdfs.rollsize = 0*
>> *a1.sinks.k1.hdfs.rollCount = 20   *
>> *a1.sinks.k1.hdfs.rollInterval = 0*
>>
>>
>> # Channel the sink connects to
>> a1.sinks.k1.channel = c1
>>
>>
>> ################describe the channel##################
>> # use a channel which buffers events in memory
>> a1.channels.c1.type = memory
>> a1.channels.c1.byteCapacity = 0
>>
>>
>> Please any help would be greatly appreciated, I have been stuck on this
>> for 2 days.
>>
>> regards,
>>
>> Chris
>>
>>
>>
>>
>>
>>
>

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