使用 IntelliJ 或 Play 时，如何使“Java Hot Spot MaxPermSize”警告消失？

How do I make the "Java Hot Spot MaxPermSize" warning go away when using IntelliJ or Play?

提问by W.P. McNeill

I get this warning when I launch IntelliJ or run playin a Playproject.

当我启动 IntelliJ 或play在Play项目中运行时，我收到此警告。

Java HotSpot(TM) 64-Bit Server VM warning: ignoring option MaxPermSize=512M; support was removed in 8.0

How do I make it go away?

我该如何让它消失？

The answerto the same question for Maven says to remove MaxPermSizeoption from the MAVEN_OPTSenvironment variable. I don't have a MAVEN_OPTSvariable set on my machine. I imagine there is some similar sbt setting, but I don't know where it is.

Maven 的同一问题的答案是MaxPermSize从MAVEN_OPTS环境变量中删除选项。MAVEN_OPTS我的机器上没有设置变量。我想有一些类似的 sbt 设置，但我不知道它在哪里。

I see lots of explanationsabout what the change to Java is, but I don't see any tips for how to make this warning go away when working with Scala.

我看到很多关于 Java 变化的解释，但我没有看到有关如何在使用 Scala 时消除此警告的任何提示。

OS X 10.9.4. Scala 2.11.1. sbt 0.13.5

OS X 10.9.4。斯卡拉 2.11.1。sbt 0.13.5

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Basically what I'm asking is "Where are all the places on my system MaxPermSizemight get set?"

基本上我要问的是“我系统上的所有位置都在哪里MaxPermSize设置？”

I don't have a sbt-launch-lib.bashset on my machine.

sbt-launch-lib.bash我的机器上没有设置。

I did find MaxPermSizeScala->JVM Parameters option of IntelliJ. Removing that makes the warning go away in IntelliJ.

我确实找到MaxPermSize了 IntelliJ 的 Scala->JVM 参数选项。删除它会使警告在 IntelliJ 中消失。

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Changed question. I originally said that this happened for SBT. (Some of the comments below address this.) This was an error on my part. It doesn't happen when I run SBT, only when I run playfrom the command line.

改变了问题。我最初说这发生在 SBT 上。（下面的一些评论解决了这个问题。）这是我的一个错误。当我运行 SBT 时不会发生这种情况，只有当我从命令行运行时才会发生这种情况play。

Is it a known bug for Play to specify the MaxPermSizeparameter? Is there a way to make it stop?

Play 指定MaxPermSize参数是一个已知的错误吗？有没有办法让它停止？

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I don't think this is a duplicate of PermGen elimination in jdk 8. That thread describes why the warning appears but does not explain how to change the IntelliJ or Play configurations to make it no longer appear.

我不认为这是jdk 8中PermGen 消除的重复。该线程描述了警告出现的原因，但没有解释如何更改 IntelliJ 或 Play 配置以使其不再出现。

回答by Jigar Joshi

This warns that you are still assuming that this flag you are passing in would work but this flag has been removed from 1.8 onward, there is no perm space in jvm 1.8 onwards

这警告您仍然假设您传入的这个标志会起作用，但是这个标志已经从 1.8 开始被删除，在 jvm 1.8 之后没有永久空间

so to get rid of this warning remove -XX:MaxPermSizefrom all the places which passes it to jvm from sbt

所以要摆脱这个警告，请-XX:MaxPermSize从所有将它从 sbt 传递给 jvm 的地方删除

For example, on Windows you just need to edit the file C:\Program Files (x86)\sbt\conf\sbtconfig.txtand edit to change it to comment the XX:MaxPermSize=256M. For example:

例如，在 Windows 上，您只需要编辑文件C:\Program Files (x86)\sbt\conf\sbtconfig.txt并编辑以将其更改为注释XX:MaxPermSize=256M. 例如：

-Xmx512M

#Commented parameter as it is deprecated on jvm 1.8 onwards
#-XX:MaxPermSize=256m

-XX:ReservedCodeCacheSize=128m

# Set the extra SBT options
-Dsbt.log.format=true

回答by lpiepiora

Sbt reads the settings from $SBT_LAUNCHER_HOME/sbt-launch-lib.bash.

Sbt 从$SBT_LAUNCHER_HOME/sbt-launch-lib.bash.

You can find following fragment, and remove -XX:MaxPermSize=${perm}m.

您可以找到以下片段，并删除-XX:MaxPermSize=${perm}m.

get_mem_opts () {
  local mem=${1:-1024}
  local perm=$(( $mem / 4 ))
  (( $perm > 256 )) || perm=256
  (( $perm < 1024 )) || perm=1024
  local codecache=$(( $perm / 2 ))

  echo "-Xms${mem}m -Xmx${mem}m -XX:MaxPermSize=${perm}m -XX:ReservedCodeCacheSize=${codecache}m"
}

PS. On windows it's in conf/sbtconfig.txt.

附注。在 Windows 上，它位于conf/sbtconfig.txt.

回答by David Keen

You may see this warning when IntelliJ is loading the project. You can stop this warning by removing any -XX:MaxPermSizevalues from the SBT settings in Preferences > "VM parameters".

当 IntelliJ 加载项目时，您可能会看到此警告。您可以通过-XX:MaxPermSize从首选项 >“VM 参数”中的 SBT 设置中删除任何值来停止此警告。

The actual JVM options used when running a Play2 app in IntelliJ don't seem to be exposed in the interface but you can edit your workspace.xmlfile manually. Look for the play2JvmOptionssetting:

在 IntelliJ 中运行 Play2 应用程序时使用的实际 JVM 选项似乎并未在界面中公开，但您可以workspace.xml手动编辑文件。查找play2JvmOptions设置：

<setting name="play2JvmOptions" value="-Xms512M -Xmx1024M -Xss1M -XX:+CMSClassUnloadingEnabled -XX:MaxPermSize=256M" />

and remove the -XX:MaxPermSizevalue.

并删除该-XX:MaxPermSize值。

Whether you think it's worth messing with your workspace.xml for the sake of a warning is up to you...

您是否认为值得为了警告而弄乱您的 workspace.xml 取决于您...

回答by f1v3

I know it's an old question, but if you're using IntelliJ, this entry:

我知道这是一个老问题，但如果您使用的是 IntelliJ，则此条目：

-XX:MaxPermSize=512m

can also be found in one of these files:

也可以在以下文件之一中找到：

PATH_TO_INTELLIJ\bin\idea.exe.vmoptions
PATH_TO_INTELLIJ\bin\idea64.exe.vmoptions

Maybe removing it there could help?

也许在那里删除它会有所帮助？

回答by Ramadas

The -XX:MaxPermSize option is specified on the "build" file inside the play framework installation folder. Removing the MaxPermSize entry removed the warning when running play project.

-XX:MaxPermSize 选项在 play 框架安装文件夹内的“build”文件中指定。删除 MaxPermSize 条目删除了运行 play 项目时的警告。

eg: /play-2.2.1/framework/build

例如：/play-2.2.1/framework/build

回答by durp

In IntelliJ, some default run configurations include specific VM paramters.

在 IntelliJ 中，一些默认运行配置包括特定的 VM 参数。

For example, the default SBT Task run configuration VM parameters include the setting "-XX:MaxPermSize=256M"

例如，默认的 SBT 任务运行配置 VM 参数包括设置“-XX:MaxPermSize=256M”

You can simply remove this entry from the default or from your custom run config and no more warnings will appear.

您可以简单地从默认值或自定义运行配置中删除此条目，并且不会出现更多警告。

回答by Amit

Actually its very easy JAVA-8 has deprecated MaxPermSize, what you need to do is simply edit your vmoptions file and replace

实际上它很容易 JAVA-8 已弃用 MaxPermSize，您需要做的只是编辑您的 vmoptions 文件并替换

-XX:MaxPermSize by -XX:MaxMetaspaceSize=128m

回答by Brideau

For anybody experiencing this on OS X/macOS, the solution for me was to go to the menu IntelliJ IDEA > Preferences..., then to Other Settings > SBTand clear the field VM parameters.

对于在 OS X/macOS 上遇到此问题的任何人，我的解决方案是转到 menu IntelliJ IDEA > Preferences...，然后转到Other Settings > SBT并清除该字段VM parameters。

As akauppi also mentioned below, there is also another set of parameters in IntelliJ IDEA > Preferences...under Build, Execution, Deployment > Built Tools > sbt

正如下面akauppi还提到，还有另一组在参数IntelliJ IDEA > Preferences...下Build, Execution, Deployment > Built Tools > sbt

回答by sendon1982

1. Open intellij install location->bin
2. Edit idea.vmoptions or idea64.vmoptions file
3. Remove -XX:MaxPermSize=xxm
4. Save File and then restart IDEA

1. 打开intellij安装位置->bin
2. 编辑idea.vmoptions 或idea64.vmoptions 文件
3. 删除 -XX:MaxPermSize=xxm
4. 保存文件然后重启IDEA

回答by anoneironaut

Just to add to this discussion. My sbtcommand ended up being a script, I simply edited the script and removed the MaxPermSizereference.

只是为了补充这个讨论。我的sbt命令最终成为一个脚本，我只是编辑了脚本并删除了MaxPermSize引用。

I know this is about play, but searches for sbt and MaxPermSize end up here.

我知道这是关于游戏的，但搜索 sbt 和 MaxPermSize 最终会出现在这里。