RFR (XS): 8078399: Deprecate -Xoss, -Xsqnopause, -Xoptimize and -Xboundthreads options in JDK 9

Dmitry Dmitriev dmitry.dmitriev at oracle.com
Tue Jun 23 10:35:43 UTC 2015


Please review this small fix which deprecate -Xoss, -Xsqnopause, 
-Xoptimize and -Xboundthreads options in JDK 9. Also, I need a sponsor 
for this fix, who can push it.

Currently HotSpot silently ignore these 4 options. Here are description 
of these options:
"-Xoss", "-Xsqnopause", "-Xoptimize" - EVM option leaved for 
compatibility. From Java 2 SDK for Solaris Developer's Guide: "Prior to 
version 1.3.0, the production releases of the Java 2 SDK for the Solaris 
Operating Environment shipped with a virtual-machine implementation 
known as the Exact VM (EVM). Beginning with version 1.3.0, the Exact VM 
is replaced by the Java HotSpot VM.". So, from Java 1.4 EVM is not used 
as VM for JDK on Solaris and these very old flags just silently ignored 
by HotSpot.
"-Xboundthreads" - was used to bind user level threads to kernel threads 
on Solaris in case when new thread library is not available. But old T1 
libthread has been removed from Solaris in release 10. JDK9 requires 
Solaris 10u9 or higher. So, this flag become useless.

All these options are deprecated, i.e. following warning is printed when 
option is specified: "Java HotSpot(TM) 64-Bit Server VM warning: Option 
-Xoss was deprecated in version 9.0 and will likely be removed in a 
future release.". In next major release all these options can be removed.

Webrev: http://cr.openjdk.java.net/~ddmitriev/8078399/webrev.00/ 
JBS: https://bugs.openjdk.java.net/browse/JDK-8078399
Tested: JPRT


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