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Re: About jdbc channel
Hi Yanzhi,  

I am not sure what file lock you are talking about. File Channel by itself does not do any time based locking. The only locking it does is to ensure that multiple channels do not use the same data directory (so there is no issue of lock being lost - the lock file is simply deleted at channel stop).  Also, the file channel deletes files as the data gets transmitted. The file channel maxFileSize is configurable, and supports a maximum of around 1.52GB. Adding multiple HDFS sinks can improve performance too.  

What version of Flume are you using? I'd suggest trying out File Channel from trunk (or the upcoming v1.3.0). JDBC channel is generally a lot slower. I have tested Flume in various configurations and never encountered issues with the file channel. Can you give me details on the file channel problems you faced? It might be a simple config issue, and easily fixable.

As for the JDBC channel, I am not sure of a good configuration - as I have not really used it much. Please wait for someone else to reply if you still feel the JDBC channel is better.
Thanks
Hari

--  
Hari Shreedharan
On Friday, September 28, 2012 at 11:49 PM, Yanzhi.liu wrote:

> Hello Hari:
>     Thanks for your question.But,I am using jdbc channel also use the file channel.File channel has a problem when there is more than one source to the file channel transmission the filechannel the Datadir accumulation of a large number of files, the the hdfs sink can not quickly deal with these files, it will cause a file lock is lost, so that can not continue, eventually leading to the entire flume cluster comprehensive stop.In order to better monitor, I therefore joined jdbc channel, how the number of event mangodb statistics can prevent data loss.
>     So I want to get a good configuration for jdbc channel.
> My Name:
> Yanzhi Liu
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> ------------------ 原始邮件 ------------------  
> 发件人: "Hari Shreedharan"<[EMAIL PROTECTED] (mailto:[EMAIL PROTECTED])>;
> 发送时间: 2012年9月29日(星期六) 中午1:32
> 收件人: "user"<[EMAIL PROTECTED] (mailto:[EMAIL PROTECTED])>;  
> 主题: Re: About jdbc channel
>  
>  
> Is there any specific reason that you are using jdbc channel? I would recommend using the FileChannel. The File Channel is what we would currently recommend for use as a durable channel. We have improved the channel a lot in the recent weeks. To take advantage of the latest features added to the channel, you can build it and drop in the new jars, or wait for the next release, which should happen soon.  
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> Thanks,  
> Hari
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> --  
> Hari Shreedharan
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>  
> On Friday, September 28, 2012 at 9:04 PM, Yanzhi.liu wrote:
>  
> > Hello:
> >     I am using the mongodb database.My flume source is custom directory source.
> >     I am configuration with jdbc channel,but the flume.log was :
> > 2012-09-28 20:56:49,468 INFO lifecycle.LifecycleSupervisor: Stopping component: org.apache.flume.channel.jdbc.JdbcChannel@1690ab (mailto:org.apache.flume.channel.jdbc.JdbcChannel@1690ab)
> > 2012-09-28 20:56:49,612 INFO impl.JdbcChannelProviderImpl: Embedded Derby shutdown raised SQL STATE 45000 as expected.
> > 2012-09-28 20:56:49,613 INFO properties.PropertiesFileConfigurationProvider: Creating channels
> > 2012-09-28 20:56:49,613 WARN impl.JdbcChannelProviderImpl: No connection URL specified. Using embedded derby database instance.
> > 2012-09-28 20:56:49,613 WARN impl.JdbcChannelProviderImpl: Overriding values for - driver: org.apache.derby.jdbc.EmbeddedDriver, user: saconnectUrl: jdbc:derby:/home/flume/.flume/jdbc-channel/db;create=true, jdbc properties file: null, dbtype: DERBY
> > I want to know how to configuration that the jdbc channel will be run.  
> > Thanks very much!
> > My Name:
> > Yanzhi Liu
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