[英]jstat : Survivor and Eden Space capacity decrease over a period
Does anytime java(8) memory capacity decrease until JVM restart? java(8) 内存容量是否会一直减少直到 JVM 重新启动?
I am using jstat -gc to dump memory information and here is the snapshot from two days.我正在使用 jstat -gc 转储内存信息,这是两天的快照。 The second snapshot has less captaity for SC1 and EC compared to the first snapshot.与第一个快照相比,第二个快照具有更少的 SC1 和 EC 容量。
Can someone help/explain why I am seeing this behavior?有人可以帮助/解释为什么我会看到这种行为吗? is that expected?这是预期的吗?
Java version : java-1.8.0-openjdk-1.8.0.191.b12
sc1: survivor space 1 capacity
EC: eden space capacity
S0C, S1C, S0U, S1U,EC,EU,OC,OU,MC,MU,CCSC,CCSU,YGC,YGCT,FGC,FGCT,GCT
4096.0,7168.0,3968.3,0.0,123904.0,54705.9,101888.0,24165.6,62464.0,60100.6,7168.0,6618.4,30,1.314,3,0.298,1.612
5632.0,4096.0,0.0,4000.2,113152.0,56035.3,101888.0,24165.6,62720.0,60145.3,7168.0,6620.0,33,1.345,3,0.298,1.643
There is a flag that controls that: -XX:+UseAdaptiveSizePolicy
, which is enabled by default.有一个标志控制: -XX:+UseAdaptiveSizePolicy
,默认情况下启用。 What this flag does, based on the target pause time you have (you are using G1
I assume), is increase or decrease certain regions based on the heuristics it gathers.根据您拥有的目标暂停时间(我假设您正在使用G1
),此标志的作用是根据它收集的启发式增加或减少某些区域。 The best way to learn at what exactly it does is the source code of G1
itself.了解它究竟做什么的最好方法是G1
本身的源代码。
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.