基本参数
-server
-Xms6120m
-Xmx6120m
-Xmn2g
-XX:SurvivorRatio=6
-XX:PermSize=256M
-XX:MaxPermSize=256m
-Xss256k
-Dsun.jnu.encoding=UTF-8
-Dfile.encoding=UTF-8
-Xloggc:/logs/gc.log
-XX:+PrintGCDetails
-XX:+PrintGCDateStamps
-XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=/tmp/heapdump_20170318_001436.hprof
-Dcom.sun.management.jmxremote.port=1161
-Dcom.sun.management.jmxremote.ssl=false
-Dcom.sun.management.jmxremote.authenticate=false
-XX:GCTimeRatio=19
-XX:+DisableExplicitGC
-Xnoclassgc
-XX:MaxTenuringThreshold=7
-XX:ParallelGCThreads=5
-XX:+UseParNewGC
-XX:MaxGCPauseMillis=100
-XX:+UseConcMarkSweepGC
-XX:CMSFullGCsBeforeCompaction=5
java version "1.6.0_27-ea"
Java(TM) SE Runtime Environment (build 1.6.0_27-ea-b03)
Java HotSpot(TM) 64-Bit Server VM (build 20.2-b03, mixed mode)
java version "1.7.0_75"
Java(TM) SE Runtime Environment (build 1.7.0_75-b13)
Java HotSpot(TM) 64-Bit Server VM (build 24.75-b04, mixed mode)
54
2234 ~ 2925 人在线
im_dstat_54.png
jstat 参考
> jstat -gcutil `pgrep java` 3000 20
S0 S1 E O P YGC YGCT FGC FGCT GCT
20.40 0.00 72.88 45.50 13.60 1292 89.409 4 0.558 89.967
20.40 0.00 86.48 45.50 13.60 1292 89.409 4 0.558 89.967
0.00 20.68 5.25 45.59 13.60 1293 89.482 4 0.558 90.040
0.00 20.68 20.72 45.59 13.60 1293 89.482 4 0.558 90.040
0.00 20.68 39.30 45.59 13.60 1293 89.482 4 0.558 90.040
0.00 20.68 57.87 45.59 13.60 1293 89.482 4 0.558 90.040
0.00 20.68 76.50 45.59 13.60 1293 89.482 4 0.558 90.040
0.00 20.68 94.39 45.59 13.60 1293 89.482 4 0.558 90.040
21.11 0.00 13.77 45.69 13.60 1294 89.571 4 0.558 90.128
21.11 0.00 34.67 45.69 13.60 1294 89.571 4 0.558 90.128
21.11 0.00 53.67 45.69 13.60 1294 89.571 4 0.558 90.128
21.11 0.00 74.58 45.69 13.60 1294 89.571 4 0.558 90.128
21.11 0.00 93.11 45.69 13.60 1294 89.571 4 0.558 90.128
0.00 21.07 11.22 45.76 13.60 1295 89.623 4 0.558 90.180
0.00 21.07 30.31 45.76 13.60 1295 89.623 4 0.558 90.180
0.00 21.07 49.62 45.76 13.60 1295 89.623 4 0.558 90.180
0.00 21.07 66.87 45.76 13.60 1295 89.623 4 0.558 90.180
0.00 21.07 85.07 45.76 13.60 1295 89.623 4 0.558 90.180
21.04 0.00 3.02 45.84 13.60 1296 89.704 4 0.558 90.262
21.04 0.00 19.99 45.84 13.60 1296 89.704 4 0.558 90.262
68
2267 人在线
im_dstat_68.png
jstat 参考
> jstat -gcutil `pgrep java` 3000 20
S0 S1 E O P YGC YGCT FGC FGCT GCT
15.69 0.00 48.98 57.08 11.62 1456 112.987 4 0.465 113.452
15.69 0.00 71.34 57.08 11.62 1456 112.987 4 0.465 113.452
15.69 0.00 93.72 57.08 11.62 1456 112.987 4 0.465 113.452
0.00 17.58 17.98 57.15 11.62 1457 113.056 4 0.465 113.522
0.00 17.58 38.76 57.15 11.62 1457 113.056 4 0.465 113.522
0.00 17.58 62.44 57.15 11.62 1457 113.056 4 0.465 113.522
0.00 17.58 85.18 57.15 11.62 1457 113.056 4 0.465 113.522
15.36 0.00 5.48 57.23 11.62 1458 113.134 4 0.465 113.599
15.36 0.00 23.99 57.23 11.62 1458 113.134 4 0.465 113.599
15.36 0.00 41.16 57.23 11.62 1458 113.134 4 0.465 113.599
15.36 0.00 59.77 57.23 11.62 1458 113.134 4 0.465 113.599
15.36 0.00 77.74 57.23 11.62 1458 113.134 4 0.465 113.599
15.36 0.00 97.79 57.23 11.62 1458 113.134 4 0.465 113.599
0.00 15.30 16.13 57.29 11.62 1459 113.210 4 0.465 113.675
0.00 15.30 34.41 57.29 11.62 1459 113.210 4 0.465 113.675
0.00 15.30 52.48 57.29 11.62 1459 113.210 4 0.465 113.675
0.00 15.30 71.87 57.29 11.62 1459 113.210 4 0.465 113.675
0.00 15.30 92.82 57.29 11.62 1459 113.210 4 0.465 113.675
15.44 0.00 14.61 57.37 11.62 1460 113.282 4 0.465 113.748
15.44 0.00 32.86 57.37 11.62 1460 113.282 4 0.465 113.748
73
2211 ~ 2831 人在线
im_dstat_73.png
jstat 参考
[root@vm_50_73 sunchanghao]# jstat -gcutil `pgrep java` 3000 20
S0 S1 E O P YGC YGCT FGC FGCT GCT
17.67 0.00 53.93 83.99 13.50 1386 86.623 14 1.366 87.989
17.67 0.00 72.27 83.99 13.50 1386 86.623 14 1.366 87.989
17.67 0.00 93.25 83.99 13.50 1386 86.623 14 1.366 87.989
0.00 15.82 13.25 84.11 13.50 1387 86.695 14 1.366 88.061
0.00 15.82 32.82 84.11 13.50 1387 86.695 14 1.366 88.061
0.00 15.82 50.25 84.11 13.50 1387 86.695 14 1.366 88.061
0.00 15.82 68.35 84.11 13.50 1387 86.695 14 1.366 88.061
0.00 15.82 86.04 84.11 13.50 1387 86.695 14 1.366 88.061
17.83 0.00 4.08 84.26 13.50 1388 86.756 14 1.366 88.122
17.83 0.00 28.89 84.26 13.50 1388 86.756 14 1.366 88.122
17.83 0.00 49.66 84.26 13.50 1388 86.756 14 1.366 88.122
17.83 0.00 70.72 84.26 13.50 1388 86.756 14 1.366 88.122
17.83 0.00 89.46 84.26 13.50 1388 86.756 14 1.366 88.122
0.00 15.50 6.33 84.42 13.50 1389 86.819 14 1.366 88.185
0.00 15.50 26.75 84.42 13.50 1389 86.819 14 1.366 88.185
0.00 15.50 46.33 84.42 13.50 1389 86.819 14 1.366 88.185
0.00 15.50 64.08 84.42 13.50 1389 86.819 14 1.366 88.185
0.00 15.50 81.98 84.42 13.50 1389 86.819 14 1.366 88.185
17.45 0.00 0.00 84.57 13.50 1390 86.883 14 1.366 88.249
17.45 0.00 22.53 84.57 13.50 1390 86.883 14 1.366 88.249
初步分析
- CPU 20~30% 左右
- 网络吞吐接近 2~3M
- 磁盘基本无读取纯写入（log）
- 内存使用率超过70%
