8179527: Ineffective use of volatile hurts performance of Charset.atBugLevel()
OGATAK at jp.ibm.com
Tue Jun 27 08:39:10 UTC 2017
I'm working on the JDK 10 source code, but I verified JDK 8 has the same
code w.r.t. use of volatile.
Alan Bateman <Alan.Bateman at oracle.com> wrote on 2017/06/27 17:13:19:
> From: Alan Bateman <Alan.Bateman at oracle.com>
> To: Claes Redestad <claes.redestad at oracle.com>, "Langer, Christoph"
> <christoph.langer at sap.com>, Kazunori Ogata <OGATAK at jp.ibm.com>,
> 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 17:13
> Subject: Re: 8179527: Ineffective use of volatile hurts performance of
> On 27/06/2017 08:36, Claes Redestad wrote:
> > The check of Charset.atBugLevel in checkName should no longer happen
> > 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 better
> > 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 fixed
> by now. So I think it can be removed.
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