JAVA -Xms与-Xmx区别

 

http://java.sun.com/j2se/1.4.2/docs/tooldocs/solaris/java.html

xms指你的程序的初始化内存大小，xmx指定你的程序占用的最大内存。单位默认字节，可以采用k,m做为单位。

俺英文不好，xmx的最后那句没看太明白，哪个高手帮忙解释下？minus overhead amounts.？

 

原装解释： -Xms n Specify the initial size, in bytes, of the memory allocation pool. This value must be a multiple of 1024 greater than 1MB. Append the letter k or K to indicate kilobytes, or m or M to indicate megabytes. The default value is 2MB. Examples:

       -Xms6291456
       -Xms6144k
       -Xms6m
       

 

-Xmx n Specify the maximum size, in bytes, of the memory allocation pool. This value must a multiple of 1024 greater than 2MB. Append the letter k or K to indicate kilobytes, or m or M to indicate megabytes. The default value is 64MB. The upper limit for this value will be approximately 4000m on Solaris 7 and Solaris 8 SPARC platforms and 2000m on Solaris 2.6 and x86 platforms, minus overhead amounts. Examples:

       -Xmx83886080
       -Xmx81920k
       -Xmx80m