Many files in file channel data directory

I'm running Flume 1.5.0 with this configuration:

flume_test.sources = sr1
flume_test.channels = ch1
flume_test.sinks = sk1

#avro source
flume_test.sources.sr1.type = avro
flume_test.sources.sr1.channels = ch1
flume_test.sources.sr1.bind = 10.92.211.22
flume_test.sources.sr1.port = 55000
flume_test.sources.sr1.ssl = true
flume_test.sources.sr1.keystore = /nas/used_by_hadoop/hadoop-kn-p2/rdd/hadoop_keystore.jks
flume_test.sources.sr1.keystore-password = *****
flume_test.sources.sr1.compression-type = gzip

#custom interceptor
flume_test.sources.sr1.interceptors = i1
flume_test.sources.sr1.interceptors.i1.type = com.vm.rdd.TimeBodyInterceptor$Builder

#memory channel
flume_test.channels.ch1.type = file
flume_test.channels.ch1.checkpointDir = /hadoop/user/flume/channels/flumeTest/checkpoint
flume_test.channels.ch1.dataDirs = /hadoop/user/flume/channels/flumeTest/data
flume_test.channels.ch1.capacity = 100000000
flume_test.channels.ch1.transactionCapacity = 10000
flume_test.channels.ch1.maxFileSize = 10000000

#HDFS channel
flume_test.sinks.sk1.channel = ch1
flume_test.sinks.sk1.type = hdfs
#dynamic path
flume_test.sinks.sk1.hdfs.path = hdfs:///landing/data/flumeTest/%Y-%m-%d
flume_test.sinks.sk1.hdfs.inUsePrefix = _
flume_test.sinks.sk1.hdfs.codeC = gzip
#write at this block size when reach it
flume_test.sinks.sk1.hdfs.rollSize = 2560000000
# roll file every 2 minutes if not filled a block
flume_test.sinks.sk1.hdfs.rollInterval = 120
# if file has been idle for 15s, close file
flume_test.sinks.sk1.hdfs.idleTimeout = 15
flume_test.sinks.sk1.hdfs.rollCount = 0
flume_test.sinks.sk1.hdfs.batchSize = 100

When I look at the data dir, there are many files:

-rw-r--r-- 1 rdd rdd 0 Jan 13 12:06 in_use.lock
-rw-r--r-- 1 rdd rdd 1.0M Jan 13 12:09 log-1
-rw-r--r-- 1 rdd rdd 1.0M Jan 13 12:09 log-2
-rw-r--r-- 1 rdd rdd 1.0M Jan 13 12:09 log-3
-rw-r--r-- 1 rdd rdd 1.0M Jan 13 12:09 log-4
-rw-r--r-- 1 rdd rdd 1.0M Jan 13 12:09 log-5
-rw-r--r-- 1 rdd rdd 1.0M Jan 13 12:09 log-6
-rw-r--r-- 1 rdd rdd 1.0M Jan 13 12:09 log-7
-rw-r--r-- 1 rdd rdd 1.0M Jan 13 12:09 log-8
-rw-r--r-- 1 rdd rdd 1.0M Jan 13 12:09 log-9
-rw-r--r-- 1 rdd rdd 1.0M Jan 13 12:09 log-10
-rw-r--r-- 1 rdd rdd 1.0M Jan 13 12:09 log-11
-rw-r--r-- 1 rdd rdd 1.0M Jan 13 12:09 log-12
-rw-r--r-- 1 rdd rdd 47 Jan 13 12:09 log-13.meta
-rw-r--r-- 1 rdd rdd 47 Jan 13 12:09 log-1.meta
-rw-r--r-- 1 rdd rdd 47 Jan 13 12:09 log-2.meta
-rw-r--r-- 1 rdd rdd 47 Jan 13 12:09 log-3.meta
-rw-r--r-- 1 rdd rdd 47 Jan 13 12:09 log-4.meta
-rw-r--r-- 1 rdd rdd 47 Jan 13 12:09 log-5.meta
-rw-r--r-- 1 rdd rdd 47 Jan 13 12:09 log-6.meta
-rw-r--r-- 1 rdd rdd 47 Jan 13 12:09 log-7.meta
-rw-r--r-- 1 rdd rdd 47 Jan 13 12:09 log-8.meta
-rw-r--r-- 1 rdd rdd 47 Jan 13 12:09 log-9.meta
-rw-r--r-- 1 rdd rdd 47 Jan 13 12:09 log-10.meta
-rw-r--r-- 1 rdd rdd 47 Jan 13 12:09 log-11.meta
-rw-r--r-- 1 rdd rdd 47 Jan 13 12:09 log-12.meta
-rw-r--r-- 1 rdd rdd 1.0M Jan 13 12:09 log-13
-rw-r--r-- 1 rdd rdd 1.0M Jan 13 12:09 log-14
-rw-r--r-- 1 rdd rdd 47 Jan 13 12:09 log-14.meta
-rw-r--r-- 1 rdd rdd 0 Jan 13 12:15 log-15
-rw-r--r-- 1 rdd rdd 47 Jan 13 12:15 log-15.meta

This list can grow up to hundreds of log files which are all accessed around the same time. When looking in the log file, it appears that the channels are duplicates of one another, as the agent is writing to each channel at the same time, for example:

2015-01-13 12:09:52,451 (Log-BackgroundWorker-ch1) [INFO - org.apache.flume.channel.file.Log.writeCheckpoint(Log.java:1005)] Updated checkpoint for file: /hadoop/user/flume/channels/flumeTest/data/log-14 position: 120431 logWriteOrderID: 1421150977639
2015-01-13 12:09:52,451 (Log-BackgroundWorker-ch1) [DEBUG - org.apache.flume.channel.file.Log.removeOldLogs(Log.java:1067)] Files currently in use: [14]
2015-01-13 12:09:52,451 (Log-BackgroundWorker-ch1) [INFO - org.apache.flume.channel.file.LogFile$RandomReader.close(LogFile.java:504)] Closing RandomReader /hadoop/user/flume/channels/flumeTest/data/log-1
2015-01-13 12:09:52,456 (Log-BackgroundWorker-ch1) [INFO - org.apache.flume.channel.file.LogFile$RandomReader.close(LogFile.java:504)] Closing RandomReader /hadoop/user/flume/channels/flumeTest/data/log-2
2015-01-13 12:09:52,461 (Log-BackgroundWorker-ch1) [INFO - org.apache.flume.channel.file.LogFile$RandomReader.close(LogFile.java:504)] Closing RandomReader /hadoop/user/flume/channels/flumeTest/data/log-3
2015-01-13 12:09:52,467 (Log-BackgroundWorker-ch1) [INFO - org.apache.flume.channel.file.LogFile$RandomReader.close(LogFile.java:504)] Closing RandomReader /hadoop/user/flume/channels/flumeTest/data/log-4
2015-01-13 12:09:52,472 (Log-BackgroundWorker-ch1) [INFO - org.apache.flume.channel.file.LogFile$RandomReader.close(LogFile.java:504)] Closing RandomReader /hadoop/user/flume/channels/flumeTest/data/log-5
2015-01-13 12:09:52,477 (Log-BackgroundWorker-ch1) [INFO - org.apache.flume.channel.file.LogFile$RandomReader.close(LogFile.java:504)] Closing RandomReader /hadoop/user/flume/channels/flumeTest/data/log-6
2015-01-13 12:09:52,482 (Log-BackgroundWorker-ch1) [INFO - org.apache.flume.channel.file.LogFile$RandomReader.close(LogFile.java:504)] Closing RandomReader /hadoop/user/flume/channels/flumeTest/data/log-7
2015-01-13 12:09:52,487 (Log-BackgroundWorker-ch1) [INFO - org.apache.flume.channel.file.LogFile$RandomReader.close(LogFile.java:504)] Closing RandomReader /hadoop/user/flume/channels/flumeTest/data/log-8
2015-01-13 12:09:52,492 (Log-BackgroundWorker-ch1) [INFO - org.apache.flume.channel.file.LogFile$RandomReader.close(LogFile.java:504)] Closing RandomReader /hadoop/user/flume/channels/flumeTest/data/log-9
2015-01-13 12:09:52,497 (Log-BackgroundWorker-ch1) [INFO - org.apache.flume.channel.file.LogFile$RandomReader.close(LogFile.java:504)] Closing RandomReader /hadoop/user/flume/channels/flumeTest/data/log-10
2015-01-13 12:09:52,503 (Log-BackgroundWorker-ch1) [INFO - org.apache.flume.channel.file.LogFile$RandomReader.close(LogFile.java:504)] Closing RandomReader /hadoop/user/flume/channels/flumeTest/data/log-11
2015-01-13 12:09:52,508 (Log-BackgroundWorker-ch1) [INFO - org.apache.flume.channel.file.LogFile$RandomReader.close(LogFile.java:504)] Closing RandomReader /hadoop/user/flume/channels/flumeTest/data/log-12
Does anyone know why there are so many active files at one time? Is this expected behaviour?

Regards,

Guy Needham | Data Discovery
Virgin Media | Technology and Transformation | Data
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