jstat -printcompilation pid
can get information about the last method that is compiled, like:
Compiled Size Type Method
207 64 1 java/lang/CharacterDataLatin1 toUpperCase
208 5 1 java/math/BigDecimal$StringBuilderHelper getCharArray
What's the third column mean? I can't find detail info about 'Type'. How many types inclued?
https://docs.oracle.com/javase/9/tools/jstat.htm#JSWOR734
oracle document dont' have enough info yet
The value in Type column corresponds to this enum:
1 = normal_compile // Regular JIT compilation
2 = osr_compile // On-stack replacement
3 = native_compile // Compiled wrapper for a native method
However, the values other than normal_compile are available only in debug builds of the JVM when -XX:+CICountOSR or -XX:+CICountNative option is set:
int last_compile_type = normal_compile;
if (CICountOSR && is_osr) {
last_compile_type = osr_compile;
} else if (CICountNative && method->is_native()) {
last_compile_type = native_compile;
}
In practice this means that Type is always 1 with a regular JDK.