The Java PrintFlagsFinal Java/JVM option (maxpermsize, maxheapsize)

As a quick note, I saw the PrintFlagsFinal Java/JVM option today, and thought it was interesting. I saw this command:

java -XX:+PrintFlagsFinal -Xmx64m -Xms32m -version 2>&1 | grep -i -E 'heapsize|permsize|version'

which yielded this output:

uintx AdaptivePermSizeWeight               = 20               {product}
uintx ErgoHeapSizeLimit                    = 0                {product}
uintx InitialHeapSize                     := 66328448         {product}
uintx LargePageHeapSizeThreshold           = 134217728        {product}
uintx MaxHeapSize                         := 1063256064       {product}
uintx MaxPermSize                          = 67108864         {pd product}
uintx PermSize                             = 16777216         {pd product}
java version "1.6.0_24"

Of course the grep part is optional; try the java command without the grep to see all of the output.

I found this command on this SO link.