RFR (S): 8181785: Remove the experimental ClearFPUAtPark JVM Flag

Thomas Schatzl thomas.schatzl at oracle.com
Fri Jun 9 12:27:06 UTC 2017

Hi Erik,

On Thu, 2017-06-08 at 17:04 +0200, Erik Österlund wrote:
> Hi,
> There is an experimental JVM flag called ClearFPUAtPark that is used 
> only by SPARC. It is turned off by default and is marked as Unsafe
> and 
> Unstable.
> The idea is to tell the Solaris kernel not to save floating point 
> registers when context switching.
> I propose to remove it as it is an unstable option. It relies on an 
> implicit unstable OS contract with the kernel that may or may not be 
> honored.
> Bug: https://bugs.openjdk.java.net/browse/JDK-8181785
> Webrev: http://cr.openjdk.java.net/~eosterlund/8181785/webrev.00/
> Testing: JPRT
> Will need a sponsor.

  looks good apart from copyright dates.

As even experimental VM options are part of the public VM interface, I
think you need to do a CSR request.

Further I think we can't just remove these options but need to use the
usual option deprecation/removal process.


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