8179527: Ineffective use of volatile hurts performance of Charset.atBugLevel()
christoph.langer at sap.com
Wed Jun 28 06:45:41 UTC 2017
this looks fine.
The copyright year in Charset-X-Coder.java.template needs to be updated, but I can do that when I push it.
Waiting for another review...
> -----Original Message-----
> From: Kazunori Ogata [mailto:OGATAK at jp.ibm.com]
> Sent: Mittwoch, 28. Juni 2017 08:21
> To: Langer, Christoph <christoph.langer at sap.com>
> Cc: Alan Bateman <Alan.Bateman at oracle.com>; Claes Redestad
> <claes.redestad at oracle.com>; core-libs-dev <core-libs-
> dev at openjdk.java.net>; nio-dev at openjdk.java.net; ppc-aix-port-
> dev at openjdk.java.net
> Subject: RE: 8179527: Ineffective use of volatile hurts performance of
> Hi Christoph,
> Thank you for your suggestions and offering to sponsor my changes.
> Here is the updated webrev that removes the atBugLevel() definition in
> Charset.java and its call sites in Charset.java and
> Charset-X-Coder.java.template. Please review this:
> "Langer, Christoph" <christoph.langer at sap.com> wrote on 2017/06/28
> > From: "Langer, Christoph" <christoph.langer at sap.com>
> > To: Alan Bateman <Alan.Bateman at oracle.com>, Kazunori Ogata
> <OGATAK at jp.ibm.com>
> > Cc: "ppc-aix-port-dev at openjdk.java.net" <ppc-aix-port-
> > dev at openjdk.java.net>, Claes Redestad <claes.redestad at oracle.com>,
> > libs-dev <core-libs-dev at openjdk.java.net>, "nio-dev at openjdk.java.net"
> > <nio-dev at openjdk.java.net>
> > Date: 2017/06/28 03:32
> > Subject: RE: 8179527: Ineffective use of volatile hurts performance of
> > Charset.atBugLevel()
> > Hi Ogata,
> > I think I agree with Alan that the Charset.atBugLevel() method can
> > completely be eliminated from java/nio/charset.
> > Ogata, would you respin your change to remove it and post it for review?
> > can then sponsor it for you.
> > @Alan: Do we need a CSR ("Compatibility & Specification Review") request
> > here since support for "sun.nio.cs.bugLevel" will be removed?
> > Best regards
> > Christoph
> > > -----Original Message-----
> > > From: Alan Bateman [mailto:Alan.Bateman at oracle.com]
> > > Sent: Dienstag, 27. Juni 2017 10:13
> > > To: Claes Redestad <claes.redestad at oracle.com>; 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
> > > Cc: ppc-aix-port-dev at openjdk.java.net
> > > Subject: Re: 8179527: Ineffective use of volatile hurts performance of
> > > Charset.atBugLevel()
> > >
> > > On 27/06/2017 08:36, Claes Redestad wrote:
> > > >
> > > > The check of Charset.atBugLevel in checkName should no longer
> > > > for the majority of situations, as that test is now only done if the
> > > > charset name is "" (see
> > > > https://bugs.openjdk.java.net/browse/JDK-8174831),
> > > Kazunori's mail didn't mention the JDK build he is using, it may have
> > > been JDK 8 rather than JDK 9.
> > >
> > > > since what differs between 1.4 and 1.5 was apparently whether or not
> > > > the empty string was to be accepted as a valid Charset...
> > > >
> > > > So yes, if we can get rid of the test altogether, we'll be even
> > > > off!
> > > JDK-4786884 is the original issue. If there was any code dependent on
> > > the broken behavior in 1.4 then I would expect it should have been
> > > by now. So I think it can be removed.
> > >
> > > -Alan
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