Fw: 8179527: Ineffective use of volatile hurts performance of Charset.atBugLevel()

[Kazunori Ogata]

Hi,

I'm re-posting this mail because I sent the old one before I subscribe 
core-libs-dev and nio-dev.

Sorry if you receive this mail twice.

Regards,
Ogata

----- Forwarded by Kazunori Ogata/Japan/IBM on 2017/06/27 17:28 -----

"ppc-aix-port-dev" <ppc-aix-port-dev-bounces at openjdk.java.net> wrote on 
2017/06/27 17:12:45:

> From: "Kazunori Ogata" <OGATAK at jp.ibm.com>
> To: Aleksey Shipilev <shade at redhat.com>
> Cc: core-libs-dev <core-libs-dev at openjdk.java.net>, "nio-
> dev at openjdk.java.net" <nio-dev at openjdk.java.net>, "ppc-aix-port-
> dev at openjdk.java.net" <ppc-aix-port-dev at openjdk.java.net>
> Date: 2017/06/27 17:13
> Subject: Re: 8179527: Ineffective use of volatile hurts performance of 
> Charset.atBugLevel()
> Sent by: "ppc-aix-port-dev" <ppc-aix-port-dev-bounces at openjdk.java.net>
> 
> Hi Christoph, 
> 
> Thank you for redirecting this request to appropriate mailing lists.
> 
> 
> Hi Aleksey,
> 
> Thank you for reviewing the patch.
> 
> 
> Regards,
> Ogata
> 
> 
> Aleksey Shipilev <shade at redhat.com> wrote on 2017/06/27 15:58:56:
> 
> > From: Aleksey Shipilev <shade at redhat.com>
> > To: "Langer, Christoph" <christoph.langer at sap.com>, Kazunori Ogata 
> > <OGATAK at jp.ibm.com>, core-libs-dev <core-libs-dev at openjdk.java.net>, 
> "nio-
> > dev at openjdk.java.net" <nio-dev at openjdk.java.net>
> > Cc: "ppc-aix-port-dev at openjdk.java.net" 
> <ppc-aix-port-dev at openjdk.java.net>
> > Date: 2017/06/27 15:59
> > Subject: Re: 8179527: Ineffective use of volatile hurts performance of 

> > Charset.atBugLevel()
> > 
> > On 06/27/2017 08:50 AM, Langer, Christoph wrote:
> > > So, waiting for comments from other experts...
> > 
> > >> Webrev: http://cr.openjdk.java.net/~horii/8179527/webrev.00/
> > 
> > This patch is fine as stated.
> > 
> > Without volatile, there is a benign data race on the bugLevel field, 
> which is
> > okay, assuming "sun.nio.cs.bugLevel" never actually changes. Doing
> > double-checked-locking seems excessive here, because we can accept 
more 
> than one
> > invocation of privilegedGetProperty.
> > 
> > -Aleksey
> > 
> > 
> > 
> > 
> > [attachment "signature.asc" deleted by Kazunori Ogata/Japan/IBM] 
>