内存溢出问题

你们python api用http连接es，连得都是协调节点吗，连多台他会自动负载均衡吧？
插入数据时协调节点为什么压力会那么大老内存溢出？数据难道会先加载到协调节点？
我连4台挂了2台, 4台机器都是配置64g，绝对超不过64g的，不知道是为什么挂的，可能是并发量太大了？
我插入4亿多条数据，用mapreduce， 
if len(actions) == 9000:
    for i in helpers.parallel_bulk(es, actions,
                             thread_count=3, chunk_size=3000):
 
[2017-12-16T22:05:43,000][WARN ][o.e.m.j.JvmGcMonitorService] [es_0 ] [gc][110776] overhead, spent [9.7s] collecting in the last [9.8s]
[2017-12-16T22:05:43,000][DEBUG][o.e.x.m.MonitoringService] [es_0 ] monitoring execution is skipped until previous execution terminated
[2017-12-16T22:05:43,000][DEBUG][i.n.b.PoolThreadCache    ] Freed 10 thread-local buffer(s) from thread: threadDeathWatcher-2-1
[2017-12-16T22:05:43,000][ERROR][o.e.t.n.Netty4Utils      ] fatal error on the network layer
        at org.elasticsearch.transport.netty4.Netty4Utils.maybeDie(Netty4Utils.java:140)
        at org.elasticsearch.http.netty4.Netty4HttpRequestHandler.exceptionCaught(Netty4HttpRequestHandler.java:81)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:286)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:265)
        at io.netty.channel.AbstractChannelHandlerContext.fireExceptionCaught(AbstractChannelHandlerContext.java:257)
        at io.netty.channel.ChannelInboundHandlerAdapter.exceptionCaught(ChannelInboundHandlerAdapter.java:131)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:286)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:265)
        at io.netty.channel.AbstractChannelHandlerContext.fireExceptionCaught(AbstractChannelHandlerContext.java:257)
        at io.netty.channel.ChannelInboundHandlerAdapter.exceptionCaught(ChannelInboundHandlerAdapter.java:131)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:286)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:265)
        at io.netty.channel.AbstractChannelHandlerContext.fireExceptionCaught(AbstractChannelHandlerContext.java:257)
        at io.netty.channel.ChannelInboundHandlerAdapter.exceptionCaught(ChannelInboundHandlerAdapter.java:131)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:286)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:265)
        at io.netty.channel.AbstractChannelHandlerContext.fireExceptionCaught(AbstractChannelHandlerContext.java:257)
        at io.netty.channel.ChannelInboundHandlerAdapter.exceptionCaught(ChannelInboundHandlerAdapter.java:131)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:286)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:265)
        at io.netty.channel.AbstractChannelHandlerContext.fireExceptionCaught(AbstractChannelHandlerContext.java:257)
        at io.netty.channel.ChannelHandlerAdapter.exceptionCaught(ChannelHandlerAdapter.java:78)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:286)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:265)
        at io.netty.channel.AbstractChannelHandlerContext.fireExceptionCaught(AbstractChannelHandlerContext.java:257)
        at io.netty.channel.ChannelInboundHandlerAdapter.exceptionCaught(ChannelInboundHandlerAdapter.java:131)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:286)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:265)
        at io.netty.channel.AbstractChannelHandlerContext.fireExceptionCaught(AbstractChannelHandlerContext.java:257)
        at io.netty.channel.ChannelInboundHandlerAdapter.exceptionCaught(ChannelInboundHandlerAdapter.java:131)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:286)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:265)
        at io.netty.channel.AbstractChannelHandlerContext.fireExceptionCaught(AbstractChannelHandlerContext.java:257)
        at io.netty.channel.ChannelInboundHandlerAdapter.exceptionCaught(ChannelInboundHandlerAdapter.java:131)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:286)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:265)
        at io.netty.channel.AbstractChannelHandlerContext.fireExceptionCaught(AbstractChannelHandlerContext.java:257)
        at io.netty.channel.DefaultChannelPipeline$HeadContext.exceptionCaught(DefaultChannelPipeline.java:1301)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:286)
        at io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:265)
        at io.netty.channel.DefaultChannelPipeline.fireExceptionCaught(DefaultChannelPipeline.java:914)
        at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.handleReadException(AbstractNioByteChannel.java:99)
        at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:140)
        at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:642)
        at io.netty.channel.nio.NioEventLoop.processSelectedKeysPlain(NioEventLoop.java:527)
        at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:481)
        at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:441)
        at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:858)
        at java.lang.Thread.run(Thread.java:745)
[2017-12-16T22:05:43,001][ERROR][o.e.b.ElasticsearchUncaughtExceptionHandler] [es_0 ] fatal error in thread [Thread-7], exiting
java.lang.OutOfMemoryError: Java heap space
[2017-12-16T22:05:43,001][WARN ][o.e.h.n.Netty4HttpServerTransport] [es_0 ] caught exception while handling client http traffic, closing connection [id: 0x383a92ab, L:/10.87.126.27:8600 - R:/10.87.195.21:39600]
java.lang.OutOfMemoryError: Java heap space
[2017-12-16T22:05:43,001][ERROR][o.e.b.ElasticsearchUncaughtExceptionHandler] [es_0 ] fatal error in thread [Thread-8], exiting
java.lang.OutOfMemoryError: Java heap space
[2017-12-16T22:05:43,001][WARN ][o.e.h.n.Netty4HttpServerTransport] [es_0 ] caught exception while handling client http traffic, closing connection [id: 0x9eee5d49, L:/10.87.126.27:8600 - R:/10.87.247.14:39292]
java.lang.OutOfMemoryError: Java heap space