On Tue, 30 Mar 2021 03:48:08 GMT, Yumin Qi <mi...@openjdk.org> wrote:
>> Hi, Please review >> >> Added jcmd option for dumping CDS archive during application runtime. >> Before this change, user has to dump shared archive in two steps: first run >> application with >> `java -XX:DumpLoadedClassList=<classlist> .... ` >> to collect shareable class names and saved in file `<classlist>` , then >> `java -Xshare:dump -XX:SharedClassListFile=<classlist> >> -XX:SharedArchiveFile=<archivefile> ...` >> With this change, user can use jcmd to dump CDS without going through >> above steps. Also user can choose a moment during the app runtime to dump >> an archive. >> The bug is associated with the CSR: >> https://bugs.openjdk.java.net/browse/JDK-8259798 which has been approved. >> New added jcmd option: >> `jcmd <pid or AppName> VM.cds static_dump <filename>` >> or >> `jcmd <pid or AppName> VM.cds dynamic_dump <filename>` >> To dump dynamic archive, requires start app with newly added flag >> `-XX:+RecordDynamicDumpInfo`, with this flag, some information related to >> dynamic dump like loader constraints will be recorded. Note the dumping >> process changed some object memory locations so for dumping dynamic archive, >> can only done once for a running app. For static dump, user can dump >> multiple times against same process. >> The file name is optional, if the file name is not supplied, the file >> name will take format of `java_pid<number>_static.jsa` or >> `java_pid<number>_dynamic.jsa` for static and dynamic respectively. The >> `<number>` is the application process ID. >> >> Tests: tier1,tier2,tier3,tier4 >> >> Thanks >> Yumin > > Yumin Qi has updated the pull request incrementally with one additional > commit since the last revision: > > Remove CDS.getVMArguments, changed to use VM.getRuntimeVMArguments. Removed > unused function from ClassLoader. Improved InstanceKlass::is_shareable() and > related test. Added more test scenarios. src/java.base/share/classes/jdk/internal/misc/CDS.java line 311: > 309: // done, delete classlist file. > 310: if (fileList.exists()) { > 311: // fileList.delete(); Is the comment unintentional? ------------- PR: https://git.openjdk.java.net/jdk/pull/2737
