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最新推荐文章于 2024-05-05 17:56:06 发布

原创最新推荐文章于 2024-05-05 17:56:06 发布 · 638 阅读

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1.jvm崩溃

Heap:
 PSYoungGen      total 543232K, used 373572K [0x0000000615580000, 0x000000064c280000, 0x00000007c0000000)
  eden space 456704K, 62% used [0x0000000615580000,0x0000000626e26e18,0x0000000631380000)
  from space 86528K, 99% used [0x0000000631a80000,0x0000000636eaa270,0x0000000636f00000)
  to   space 220672K, 0% used [0x000000063eb00000,0x000000063eb00000,0x000000064c280000)
 ParOldGen       total 986112K, used 252338K [0x00000002c0000000, 0x00000002fc300000, 0x0000000615580000)
  object space 986112K, 25% used [0x00000002c0000000,0x00000002cf66c828,0x00000002fc300000)
 Metaspace       used 46158K, capacity 47952K, committed 48128K, reserved 1091584K
  class space    used 5491K, capacity 5866K, committed 5888K, reserved 1048576K

可以看出From Survivor空间内存不足，通过调整Survivor区内存可以解决,最终，内存调整为8G才解决问题。
java -Xmx20g -Xms20g -XX:NewSize=8g -jar xx.jar
之后，jvm还是继续崩溃，查看崩溃日志：

Current thread is native thread

siginfo: si_signo: 11 (SIGSEGV), si_code: 1 (SEGV_MAPERR), si_addr: 0x00007fd0156f7000

Registers:
RAX=0xfffffffffffff200, RBX=0x00007fd09ca2df48, RCX=0x00007fd0156f7000, RDX=0x00007fce88bfb6e0
RSP=0x00007fd09ca2b000, RBP=0xfffffffffffffc80, RSI=0x00007fd09ca2be90, RDI=0x00007fd0156fa840
R8 =0x00007fd015817e00, R9 =0x00007fce88c0b5e0, R10=0x0000000000007f80, R11=0x0000000000000030
R12=0x00000000000000e0, R13=0x0000000000000300, R14=0x0000000000000010, R15=0x00007fce88beb7e0
RIP=0x00007fd0d7c601a0, EFLAGS=0x0000000000010287, CSGSFS=0x8084000000000033, ERR=0x0000000000000004
  TRAPNO=0x000000000000000e

一个非预期的错误被 JRE 检测到，通过添加参数-XX:-ReduceInitialCardMarks问题解决。最终的运行指令：

java -Xmx20g -Xms20g -XX:NewSize=8g -XX:-ReduceInitialCardMarks -jar xx.jar

Tomcat 7无法访问中文名称的资源
修改 Tomcat 的 server.xml 文件，在 8080端口所在的Connector 标签中加个 URIEncoding=“UTF-8” 属性。
div高宽比设置
https://segmentfault.com/a/1190000004231995

linux使用yum安装完jdk后
jdk的默认安装位置在/usr/lib/jvm

echo export JAVA_HOME=/usr/lib/jvm/jre >> ~/.bashrc
source ~/.bashrc

mysql授权

grant all privileges on *.* to 'root'@'%' identified by 'root'