[crac] RFR: Allow users to pass new properties on restore [v9]

Anton Kozlov akozlov at openjdk.java.net
Thu May 26 13:25:09 UTC 2022


On Wed, 25 May 2022 14:52:17 GMT, Ashutosh Mehra <duke at openjdk.java.net> wrote:

>> VM changes: To identify properties that can be modified on restore,
>> added a new bool field SystemProperty::_modifiable_on_restore.
>> All the jdk related properties are marked unmodifiable. Rest of the
>> properties are considered modifiable.
>> When the JVM is launched with -XX:CRaCRestoreFrom option, then the
>> properties prefixed with "-D" are maintained in a separate list in
>> Arguments::_system_properties_for_restore. This list is passed to the JVM
>> being restored by writing to a shared memory object.
>> When the JVM is restored, it reads the new properties from shared memory
>> object and updates its existing list of properties maintained in
>> Arguments::_system_properties.
>> 
>> JDK changes: System::props needs to be updated on restore to account for
>> new system properties. For this purpose j.l.System registers a new
>> JDKResource which queries new properties from the VM in afterRestore()
>> notification and updates System::props. The JDKResource registered by
>> j.l.System is given highest priority so it is the first resource to get
>> afterRestore() notification.
>> 
>> Signed-off-by: Ashutosh Mehra <asmehra at redhat.com>
>
> Ashutosh Mehra has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Rename VM_CracRestoreParameters to CracRestoreParameters
>   
>   Signed-off-by: Ashutosh Mehra <asmehra at redhat.com>

Thanks! LGTM

-------------

Marked as reviewed by akozlov (Lead).

PR: https://git.openjdk.java.net/crac/pull/21


More information about the crac-dev mailing list