If you reduce the capacity the channel will be able to buffer fewer events. If you want to reduce the space used when there are only a few events remaining set the config param: "maxFileSize" to something lower(this is in bytes). I don't advice setting this to lower than a few hundred megabytes (in fact, the default value works pretty well - do you really need to save 3GB space?)- else you will end up having a huge number of small files if there are many events wait to be taken from the channel.
Hari On Wed, Mar 20, 2013 at 12:50 AM, Zhiwen Sun <[email protected]> wrote: > Hi Hari: > > Is that means I can reduce the capacity of file channel to cut down max > disk space used by file channel? > > > Zhiwen Sun > > > > On Wed, Mar 20, 2013 at 3:23 PM, Hari Shreedharan < > [email protected]> wrote: > >> Hi, >> >> Like I mentioned earlier, we will always keep 2 data files in each data >> directory (the ".meta" files are metadata associated to the actual data). >> Once a log-8 is created(when log-7 gets rotated when it hits maximum size) >> and all of the events in log-6 are taken, then log-6 will get deleted, but >> you will still will see log-7 and log-8. So what you are seeing is not >> unexpected. >> >> >> Hari >> >> -- >> Hari Shreedharan >> >> On Tuesday, March 19, 2013 at 6:30 PM, Zhiwen Sun wrote: >> >> Thanks all for your reply. >> >> @Kenison >> I stop my tail -F | nc program and there is no new event file in HDFS, so >> I think there is no event arrive. To make sure, I will test again with >> enable JMX. >> >> @Alex >> >> The latest log is following. I can't see any exception or warning. >> >> 13/03/19 15:28:16 INFO hdfs.BucketWriter: Renaming hdfs:// >> 127.0.0.1:9000/flume/events/2013-03-19/app.1363660490901.tmp to hdfs:// >> 127.0.0.1:9000/flume/events/2013-03-19/app.1363660490901 >> 13/03/19 15:28:16 INFO hdfs.BucketWriter: Creating hdfs:// >> 127.0.0.1:9000/flume/events/2013-03-19/app.1363660490902.tmp >> 13/03/19 15:28:17 INFO file.EventQueueBackingStoreFile: Start checkpoint >> for /home/zhiwensun/.flume/file-channel/checkpoint/checkpoint, elements to >> sync = 3 >> 13/03/19 15:28:17 INFO file.EventQueueBackingStoreFile: Updating >> checkpoint metadata: logWriteOrderID: 1363659953997, queueSize: 0, >> queueHead: 362981 >> 13/03/19 15:28:17 INFO file.LogFileV3: Updating log-7.meta >> currentPosition = 216278208, logWriteOrderID = 1363659953997 >> 13/03/19 15:28:17 INFO file.Log: Updated checkpoint for file: >> /home/zhiwensun/.flume/file-channel/data/log-7 position: 216278208 >> logWriteOrderID: 1363659953997 >> 13/03/19 15:28:26 INFO hdfs.BucketWriter: Renaming hdfs:// >> 127.0.0.1:9000/flume/events/2013-03-19/app.1363660490902.tmp to hdfs:// >> 127.0.0.1:9000/flume/events/2013-03-19/app.1363660490902 >> 13/03/19 15:28:27 INFO hdfs.BucketWriter: Creating hdfs:// >> 127.0.0.1:9000/flume/events/2013-03-19/app.1363660490903.tmp >> 13/03/19 15:28:37 INFO hdfs.BucketWriter: Renaming hdfs:// >> 127.0.0.1:9000/flume/events/2013-03-19/app.1363660490903.tmp to hdfs:// >> 127.0.0.1:9000/flume/events/2013-03-19/app.1363660490903 >> 13/03/19 15:28:37 INFO hdfs.BucketWriter: Creating hdfs:// >> 127.0.0.1:9000/flume/events/2013-03-19/app.1363660490904.tmp >> >> 13/03/19 15:28:47 INFO file.EventQueueBackingStoreFile: Start checkpoint >> for /home/zhiwensun/.flume/file-channel/checkpoint/checkpoint, elements to >> sync = 2 >> 13/03/19 15:28:47 INFO file.EventQueueBackingStoreFile: Updating >> checkpoint metadata: logWriteOrderID: 1363659954200, queueSize: 0, >> queueHead: 362981 >> 13/03/19 15:28:47 INFO file.LogFileV3: Updating log-7.meta >> currentPosition = 216288815, logWriteOrderID = 1363659954200 >> 13/03/19 15:28:47 INFO file.Log: Updated checkpoint for file: >> /home/zhiwensun/.flume/file-channel/data/log-7 position: 216288815 >> logWriteOrderID: 1363659954200 >> 13/03/19 15:28:48 INFO hdfs.BucketWriter: Renaming hdfs:// >> 127.0.0.1:9000/flume/events/2013-03-19/app.1363660490904.tmp to hdfs:// >> 127.0.0.1:9000/flume/events/2013-03-19/app.1363660490904 >> >> >> @Hari >> em, 12 hours passed. The size of file channel directory has no reduce. >> >> Files in file channel directory: >> >> -rw-r--r-- 1 zhiwensun zhiwensun 0 2013-03-19 09:15 in_use.lock >> -rw-r--r-- 1 zhiwensun zhiwensun 1.0M 2013-03-19 10:11 log-6 >> -rw-r--r-- 1 zhiwensun zhiwensun 29 2013-03-19 10:12 log-6.meta >> -rw-r--r-- 1 zhiwensun zhiwensun 207M 2013-03-19 15:28 log-7 >> -rw-r--r-- 1 zhiwensun zhiwensun 29 2013-03-19 15:28 log-7.meta >> -rw-r--r-- 1 zhiwensun zhiwensun 207M 2013-03-19 15:28 >> ./file-channel/data/log-7 >> -rw-r--r-- 1 zhiwensun zhiwensun 29 2013-03-19 10:12 >> ./file-channel/data/log-6.meta >> -rw-r--r-- 1 zhiwensun zhiwensun 29 2013-03-19 15:28 >> ./file-channel/data/log-7.meta >> -rw-r--r-- 1 zhiwensun zhiwensun 0 2013-03-19 09:15 >> ./file-channel/data/in_use.lock >> -rw-r--r-- 1 zhiwensun zhiwensun 1.0M 2013-03-19 10:11 >> ./file-channel/data/log-6 >> >> >> >> >> >> >> Zhiwen Sun >> >> >> >> On Wed, Mar 20, 2013 at 2:32 AM, Hari Shreedharan < >> [email protected]> wrote: >> >> It is possible for the directory size to increase even if no writes are >> going in to the channel. If the channel size is non-zero and the sink is >> still writing events to HDFS, the takes get written to disk as well (so we >> know what events in the files were removed when the channel/agent >> restarts). Eventually the channel will clean up the files which have all >> events taken (though it will keep at least 2 files per data directory, just >> to be safe). >> >> -- >> Hari Shreedharan >> >> On Tuesday, March 19, 2013 at 10:32 AM, Alexander Alten-Lorenz wrote: >> >> Hey, >> >> what says debug? Do you can gather logs and attach them? >> >> - Alex >> >> On Mar 19, 2013, at 5:27 PM, "Kenison, Matt" <[email protected]> >> wrote: >> >> Check the JMX counter first, to make sure you really are not sending new >> events. If not, is it your checkpoint directory or data directory that is >> increasing in size? >> >> >> From: Zhiwen Sun <[email protected]> >> Reply-To: "[email protected]" <[email protected]> >> Date: Tue, 19 Mar 2013 01:19:19 -0700 >> To: "[email protected]" <[email protected]> >> Subject: Why used space of flie channel buffer directory increase? >> >> hi all: >> >> I test flume-ng in my local machine. The data flow is : >> >> tail -F file | nc 127.0.0.01 4444 > flume agent > hdfs >> >> My configuration file is here : >> >> a1.sources = r1 >> a1.channels = c2 >> >> a1.sources.r1.type = netcat >> a1.sources.r1.bind = 192.168.201.197 >> a1.sources.r1.port = 44444 >> a1.sources.r1.max-line-length = 1000000 >> >> a1.sinks.k1.type = logger >> >> a1.channels.c1.type = memory >> a1.channels.c1.capacity = 10000 >> a1.channels.c1.transactionCapacity = 10000 >> >> a1.channels.c2.type = file >> a1.sources.r1.channels = c2 >> >> a1.sources.r1.interceptors = i1 >> a1.sources.r1.interceptors.i1.type = timestamp >> >> a1.sinks = k2 >> a1.sinks.k2.type = hdfs >> a1.sinks.k2.channel = c2 >> a1.sinks.k2.hdfs.path = hdfs://127.0.0.1:9000/flume/events/%Y-%m-%d >> a1.sinks.k2.hdfs.writeFormat = Text >> a1.sinks.k2.hdfs.rollInterval = 10 >> a1.sinks.k2.hdfs.rollSize = 10000000 >> a1.sinks.k2.hdfs.rollCount = 0 >> >> a1.sinks.k2.hdfs.filePrefix = app >> a1.sinks.k2.hdfs.fileType = DataStream >> >> >> >> >> it seems that events were collected correctly. >> >> But there is a problem boring me: Used space of file channel (~/.flume) >> has always increased, even there is no new event. >> >> Is my configuration wrong or other problem? >> >> thanks. >> >> >> Best regards. >> >> Zhiwen Sun >> >> >> -- >> Alexander Alten-Lorenz >> http://mapredit.blogspot.com >> German Hadoop LinkedIn Group: http://goo.gl/N8pCF >> >> >> >> >> >
