1、專門查看java 進程的工具 jps
官網鏈接:jps官方文檔
輸入命令:jps -l
kjctar@kjctar-virtual-machine:~/Downloads/apache-tomcat-8.5.50/bin$ jps -l
5376 org.apache.catalina.startup.Bootstrap (第一個數字是pid 第二個是java進程名,這裏是tomcat)
7801 sun.tools.jps.Jps (jps命令的進程)
2、查看java進程運行時參數命令jstat
官網鏈接:jstat官方文檔
輸入命令: jstat -gc 5376 1000 10 (查看gc的內存狀態 1000ms查一次 查詢10次)
kjctar@kjctar-virtual-machine:~/Downloads/apache-tomcat-8.5.50/bin$ jstat -gc 5376 1000 10
S0C S1C S0U S1U EC EU OC OU MC MU CCSC CCSU YGC YGCT FGC FGCT GCT
2560.0 2560.0 0.0 2544.0 31744.0 16132.0 42496.0 8638.6 15104.0 14619.0 1792.0 1578.0 3 0.179 0 0.000 0.179
2560.0 2560.0 0.0 2544.0 31744.0 16132.0 42496.0 8638.6 15104.0 14619.0 1792.0 1578.0 3 0.179 0 0.000 0.179
2560.0 2560.0 0.0 2544.0 31744.0 16132.0 42496.0 8638.6 15104.0 14619.0 1792.0 1578.0 3 0.179 0 0.000 0.179
2560.0 2560.0 0.0 2544.0 31744.0 16132.0 42496.0 8638.6 15104.0 14619.0 1792.0 1578.0 3 0.179 0 0.000 0.179
2560.0 2560.0 0.0 2544.0 31744.0 16132.0 42496.0 8638.6 15104.0 14619.0 1792.0 1578.0 3 0.179 0 0.000 0.179
2560.0 2560.0 0.0 2544.0 31744.0 16132.0 42496.0 8638.6 15104.0 14619.0 1792.0 1578.0 3 0.179 0 0.000 0.179
2560.0 2560.0 0.0 2544.0 31744.0 16132.0 42496.0 8638.6 15104.0 14619.0 1792.0 1578.0 3 0.179 0 0.000 0.179
2560.0 2560.0 0.0 2544.0 31744.0 16132.0 42496.0 8638.6 15104.0 14619.0 1792.0 1578.0 3 0.179 0 0.000 0.179
2560.0 2560.0 0.0 2544.0 31744.0 16132.0 42496.0 8638.6 15104.0 14619.0 1792.0 1578.0 3 0.179 0 0.000 0.179
2560.0 2560.0 0.0 2544.0 31744.0 16132.0 42496.0 8638.6 15104.0 14619.0 1792.0 1578.0 3 0.179 0 0.000 0.179
分析內存溢出
第一步 導出內存印象文件 (有兩種方法)
- 自動導出:配置-XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=./
- 手動導出 命令
jmap -dump:format=b,file=heap.hprof 45458(進程id)