flume报错：Sinks are likely not keeping up with sources, or the buffer size is too tight

使用flume收集日志，在agent的日志中发现如下错误信息：

Caused by: org.apache.flume.ChannelException: Space for commit to queue couldn't be acquired Sinks are likely not keeping up with sources, or the buffer size is too tight
        at org.apache.flume.channel.MemoryChannel$MemoryTransaction.doCommit(MemoryChannel.java:126)
        at org.apache.flume.channel.BasicTransactionSemantics.commit(BasicTransactionSemantics.java:151)
        at org.apache.flume.channel.ChannelProcessor.processEventBatch(ChannelProcessor.java:192)
        ... 28 more

解决方法：

1）修改flume-ng agen的堆内存：

vim flume-env.sh
export JAVA_OPTS="-Xms1024m -Xmx1024m"

默认是20m

2）修改channel的配置信息：

agent1.channels.mc1.capacity = 1000
agent1.channels.mc1.keep-alive = 60

解释：

keep-alive"这个参数用来控制channel满时影响source的发送，channel空时影响sink的消费，就是等待时间，默认是3s，超过这个时间就甩异常，一般不需配置，但是有些情况很有用，比如你得场景是每分钟开头集中发一次数据，这时每分钟的开头量可能比较大，后面会越来越小，这时你可以调大这个参数，不至于出现channel满了得情况；