The current more popular several different companies different versions of the maximum memory of the JVM, the results are as follows:

The current more popular several different versions of the JVM's maximum memory:

Corporate JVM version maximum memory (mega) client maximum memory (MB) server
SUN 1.5.x 1492 1520
SUN 1.5.5 (Linux) 2634 2660
SUN 1.4.2 1564 1564
SUN 1.4.2 (Linux) 1900 1260
IBM 1.4.2 (Linux) 2047 N/A
BEA JRockit 1.5 (U3) 1909 1902


Unless otherwise stated, the JVM version runs under the Windows operating system

Attach: How to obtain the maximum available memory of the JVM

Test with the java-xmxxxxxm-version command at the command line, then gradually increase the value of XXXX, and print the error message if the specified memory size is available if performed normally.

The actual discovery version has a slight difference in the JDK maximum allowable memory value is not the same, so in the actual application or to test their own to see what the value of memory to achieve.

What this table is saying is that if your machine has too much memory, you can only use a few more instances to provide the machine's utilization, such as running Tomcat, you can pack a few more tomcat and do the cluster, and so on.