egg-logger写日志文件失败导致服务器CPU打满100%
**故障表现**：服务器CPU占用100%，导致无法处理任何请求，进程假死。

**错误日志文件**：
大量的写日志失败和reloaded错误日志：
![image](https://user-images.githubusercontent.com/12515465/117806325-c67a4700-b28c-11eb-8a83-091bd4eae688.png)

查看每分钟重启次数，在3万次左右（基本确定是这个原因导致CPU打满）：
![image](https://user-images.githubusercontent.com/12515465/117806431-edd11400-b28c-11eb-811a-f366c66e3015.png)

写一个测试js文件写入相同日志文件，写入成功，排除文件占用和权限问题：
```
const fs = require('fs');

const filename = '/root/logs/page-builder-client/page-builder-client-kafka.log';
const stream = fs.createWriteStream(filename, { flags: 'a' });
stream._onError = (err) => {
  console.error('%s ERROR %s [egg-logger] [%s] %s',
    Date(), process.pid, this.options.file, err.stack);
  this.reload();
  console.warn('%s WARN %s [egg-logger] [%s] reloaded', Date(), process.pid, this.options.file);
};
stream.write('this is a test input.', 'utf-8');
```

**问题**：这个是什么原因导致的写入失败，reload的重试没有次数限制吗，导致耗尽CPU资源，怎么处理这种问题。
相关issue问题：https://github.com/eggjs/egg/issues/4533

_附上定位问题查到的相关源代码：_
```
/**
   * reload file stream
   */
  reload() {
    this._closeStream();
    this._stream = this._createStream();
  }

/**
   * create stream
   * @return {Stream} return writeStream
   * @private
   */
  _createStream() {
    mkdirp.sync(path.dirname(this.options.file));
    const stream = fs.createWriteStream(this.options.file, { flags: 'a' });

    const onError = err => {
      console.error('%s ERROR %s [egg-logger] [%s] %s',
        utility.logDate(','), process.pid, this.options.file, err.stack);
      this.reload();
      console.warn('%s WARN %s [egg-logger] [%s] reloaded', utility.logDate(','), process.pid, this.options.file);
    };
    // only listen error once because stream will reload after error
    stream.once('error', onError);
    stream._onError = onError;
    return stream;
  }

  /**
   * close stream
   * @private
   */
  _closeStream() {
    if (this._stream) {
      this._stream.end();
      this._stream.removeListener('error', this._stream._onError);
      this._stream = null;
    }
  }
```