java - jcmd - Meaning of last colum for `jcmd VM.flags -all` -

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run following command list available jvm flags:

jcmd 24468 vm.flags -all | less -n

then in last column, found following values (using jdk1.8, on linux):

 * product     default value same on platform, * pd product     default value platform-dependent, * manageable     change dymanically in runtime, *  * c1 product * c2 product *  * c1 pd product * c2 pd product *  * product rw *  * lp64_product * arch product *  * commercial *

the question is:

  • i know meaning of values, have give explanation, meaning of rest ones?
  • anybody edit answer , create jcmd tag? don't have 1500 reputation that.

the type of flag depends on location in hotspot source code flag declared / defined. flags declared in src/share/vm/runtime/globals.hpp.

there also

  • diagnostic flags use jvm developers.
    unlocked -xx:+unlockdiagnosticvmoptions.
  • experimental flags features not tested/supported.
    unlocked -xx:+unlockexperimentalvmoptions.

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