RFR : PPC64 : Need support for VSR spills in ppc.ad

[Doerr, Martin]

Hi Gustavo,

I think the change should be tested a little longer before requesting a backport.
But in general, I'm not against it if you do all the work. Please note that I can't push to 8u (I'm not a 8u committer or reviewer).

Best regards,
Martin


-----Original Message-----
From: Gustavo Romero [mailto:gromero at linux.vnet.ibm.com] 
Sent: Mittwoch, 24. Januar 2018 13:40
To: Michihiro Horie <HORIE at jp.ibm.com>; Doerr, Martin <martin.doerr at sap.com>
Cc: Lindenmaier, Goetz <goetz.lindenmaier at sap.com>; hotspot-dev at openjdk.java.net; ppc-aix-port-dev at openjdk.java.net
Subject: Re: RFR : PPC64 : Need support for VSR spills in ppc.ad

Hi Martin,

I think Michi measured the effectivity of this change using SPECjbb2015 and got
about 4% of performance improvement in max-jOPS.

Many of our clients still use OpenJDK 8 and I understand that although currently
there isn't a new schedule ahead of 8u162 [1], 8 will continue to receive
updates once 8u162 is GA. So I would to backport it to jdk8u/jdk8u so distros
can grab it on the next security update (roughly). Are you ok with that?

If you are ok, since this change depends upon other changes that introduced the
support for VSX, is it fine if I start backporting them firstly instead
of this one? What do you recommend?

Thank you.


Regards,
Gustavo

[1] http://openjdk.java.net/projects/jdk8u/