Spring Boot应用首次启动慢的问题

绝地灬酷狼 2022-04-11 09:54 375阅读 0赞

最近一个项目中，遇到了一个奇怪的现象，spring boot应用启动后，第一次访问页面总是会有大量的ajax请求pedding，然后刷新页面，大量的`IOException`错误：

org.apache.catalina.connector.ClientAbortException: java.io.IOException: Broken pipe
            at org.apache.catalina.connector.OutputBuffer.realWriteBytes(OutputBuffer.java:356)
            at org.apache.catalina.connector.OutputBuffer.flushByteBuffer(OutputBuffer.java:815)
            at org.apache.catalina.connector.OutputBuffer.append(OutputBuffer.java:720)
            at org.apache.catalina.connector.OutputBuffer.writeBytes(OutputBuffer.java:391)
            at org.apache.catalina.connector.OutputBuffer.write(OutputBuffer.java:369)
            at org.apache.catalina.connector.CoyoteOutputStream.write(CoyoteOutputStream.java:96)
            at com.fasterxml.jackson.core.json.UTF8JsonGenerator._flushBuffer(UTF8JsonGenerator.java:2039)
            at com.fasterxml.jackson.core.json.UTF8JsonGenerator._writeBytes(UTF8JsonGenerator.java:1127)
            at com.fasterxml.jackson.core.json.UTF8JsonGenerator.writeFieldName(UTF8JsonGenerator.java:253)

这个问题存在于服务器（CentOS 7）上，在开发者机器（Windows、Mac）上无法复现，这就比较诡异了。首先想到的是日志查看法。日志级别设为debug，查看启动整个流程，没有发现明显异常，只是看到在`IOException`之前发现有连续的几行类似的日志：

[12-05 13:54:32.912| WARN|1-exec-3|o.a.catalina.util.SessionIdGeneratorBase.log:179] Creation of SecureRandom instance for session ID generation using [SHA1PRNG] took [67,400] milliseconds.
    [12-05 13:54:32.915| WARN|1-exec-2|o.a.catalina.util.SessionIdGeneratorBase.log:179] Creation of SecureRandom instance for session ID generation using [SHA1PRNG] took [67,401] milliseconds.
    [12-05 13:54:32.912| WARN|-exec-12|o.a.catalina.util.SessionIdGeneratorBase.log:179] Creation of SecureRandom instance for session ID generation using [SHA1PRNG] took [7,738] milliseconds.
    [12-05 13:54:32.917| WARN|1-exec-9|o.a.catalina.util.SessionIdGeneratorBase.log:179] Creation of SecureRandom instance for session ID generation using [SHA1PRNG] took [7,755] milliseconds.
    [12-05 13:54:32.917| WARN|1-exec-7|o.a.catalina.util.SessionIdGeneratorBase.log:179] Creation of SecureRandom instance for session ID generation using [SHA1PRNG] took [7,755] milliseconds.

这明显是在生成Session ID上消耗了太长的时间。为了证明这一点，我在页面ajax hang住期间，执行`jstack ${pid}` 命令，显示hang住期间的内存堆栈。堆栈显示如下（有精简）：

[原文链接][Link 1]

[Link 1]: http://click.aliyun.com/m/1000028233/