堆的大小是多少 jvm 使用时默认 maven 为了创造 jvm?

我使用运行以下命令的服务器。

mvn jetty:run

我想停止服务器，但我无法运行 mvn jetty: stop, 甚至没有设法运行 java -version, 为什么？

[mirror@home wpse]$ mvn jetty:stop              /////////////

Error occurred during initialization of VM

Could not reserve enough space for object heap

Could not create the Java virtual machine.

[mirror@home wpse]$ java                     //////////////

Error occurred during initialization of VM

Could not reserve enough space for object heap

Could not create the Java virtual machine.

[mirror@home wpse]$ java -version             ///////////////

Error occurred during initialization of VM

Could not reserve enough space for object heap

Could not create the Java virtual machine.

事实是我有关于 50 免费内存的MB，为什么我无法运行 java -version? 一支球队需要多少内存 java -version?

Mem:   1048800k total,   993728k used,    55072k free,        0k buffers

Swap:        0k total,        0k used,        0k free,        0k cached

问题是堆的大小 jvm 使用时默认 maven 为了创造 jvm?

怎么做 Java 使用时使用较小的束 maven?