高配服务器出现OutOfDirectMemoryError异常

[HongKing]

• [ ] I have searched the issues of this repository and believe that this is not a duplicate.

Ⅰ. Issue Description

seata-server 在开发、测试阶段都一切正常，昨天准备部署生产试运行环境时出现的。eureka注册中心，mysql数据库，启动参数及脚本采用默认的（-XX:MaxDirectMemorySize=1024m）。 出现错误后，尝试修改-XX:MaxDirectMemorySize 为2G，3G，4G都会出问题，大概接入了5个左右的微服务就爆。

能否给出一个服务器推荐配置？

Ⅱ. Describe what happened

错误日志：

2020-01-10 10:35:09.728 INFO [NettyServerNIOWorker_1_64]io.seata.core.rpc.netty.RpcServer.exceptionCaught:377 -channel exx:failed to allocate 134217728 byte(s) of direct memory (used: 1073741824, max: 1073741824),channel:[id: 0x5f464337, L:/112.128.4.29:8091 - R:/112.128.4.62:44292]2020-01-10 10:35:09.728 ERROR[NettyServerNIOWorker_1_64]io.seata.core.rpc.netty.AbstractRpcRemoting.exceptionCaught:437 -0318
io.netty.util.internal.OutOfDirectMemoryError: failed to allocate 134217728 byte(s) of direct memory (used: 1073741824, max: 1073741824)
    at io.netty.util.internal.PlatformDependent.incrementMemoryCounter(PlatformDependent.java:652)
    at io.netty.util.internal.PlatformDependent.allocateDirectNoCleaner(PlatformDependent.java:606)
    at io.netty.buffer.PoolArena$DirectArena.allocateDirect(PoolArena.java:764)
    at io.netty.buffer.PoolArena$DirectArena.newChunk(PoolArena.java:740)
    at io.netty.buffer.PoolArena.allocateNormal(PoolArena.java:244)
    at io.netty.buffer.PoolArena.allocate(PoolArena.java:214)
    at io.netty.buffer.PoolArena.allocate(PoolArena.java:146)
    at io.netty.buffer.PooledByteBufAllocator.newDirectBuffer(PooledByteBufAllocator.java:324)
    at io.netty.buffer.AbstractByteBufAllocator.directBuffer(AbstractByteBufAllocator.java:185)
    at io.netty.buffer.AbstractByteBufAllocator.directBuffer(AbstractByteBufAllocator.java:176)
    at io.netty.buffer.AbstractByteBufAllocator.ioBuffer(AbstractByteBufAllocator.java:137)
    at io.netty.channel.DefaultMaxMessagesRecvByteBufAllocator$MaxMessageHandle.allocate(DefaultMaxMessagesRecvByteBufAllocator.java:114)
    at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:147)
    at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:644)
    at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:579)
    at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:496)
    at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:458)
    at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:897)
    at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
    at java.lang.Thread.run(Thread.java:745)

Ⅲ. Describe what you expected to happen

网上都是给的netty内存溢出方案，我怀疑跟JVM内存管理有关，暂时还没有用jps详细跟踪。

Ⅳ. How to reproduce it (as minimally and precisely as possible)

1. 服务器高配（32vCPU，64G内存）
2. seata-server 1.0.0
3. 5个以上的微服务

Ⅴ. Anything else we need to know?

Ⅵ. Environment:

• JDK version : 1.8
• OS : centos 7.5
• seata-server：1.0.0

服务器配置： 开发测试：4核8G（一切正常，10多个微服务连接也没有问题） 生产试运行：32核64G（5个微服务就报错） seata-server的配置参数都一致

[HongKing]

补充：seata-server所在服务器为centos7的最小化安装，仅关闭了防火墙，其他未做任何调整

[zjinlei]

Known issues are being investigated. The recommended configuration has been implemented by default.

[zhang379988125]

配置不能解决问题，我用类似 http://www.jiangxinlingdu.com/practice/2018/09/04/netty-outofheap.html 文中的方法跟踪了代码， 问题差不多，netty建立链接时，内存统计器，做了累加，断开链接时，不会减，再重新建立链接，继续累加，默认每次分配256M，所以配置多大都不行，异常只是时间问题，本人能力有限，跟踪了断开链接的代码，没能找到解决问题的入口，期待问题得到解决

[zjinlei]

We have provided a new server startup package, please help verify it. Can be downloaded from qq group (254657148), Dingding 2 group (http://seata.io/zh-cn/community/index.html).

[slievrly]

@HongKing Can you verify if this pr fixes the problem you encountered? #2175

[HongKing]

@slievrly 已解决，强！